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Security by obscurity is underrated

• cj 6y ago
  Article is down for me. Cache: https://webcache.googleusercontent.com/search?q=cache:Bgl-exCaSzkJ:https://utkusen.com/blog/security-by-obscurity-is-underrated.html+&cd=1&hl=en&ct=clnk&gl=us https://webcache.googleusercontent.com/search?q=cache:Bgl-ex...
• jmount 6y ago
  Like the article. Security also needs to be sensitive to usability trade-offs. Make things hard for adversaries, easy for intended users. For some things, like VPNs, the adversaries are going to be more familiar with the details than the intended users. I often joke that an effective way to crack a VPN would be offer to configure it properly for a user in exchange for ten minutes of unfettered access to the target company; enough users are sufficiently frustrated they would take this bad deal fully knowing what it meant.
  • shiftpgdn 6y ago
    This is the whole "shadow IT" that actually results in a lot of security breaches. Look at the recent twitter hack for a great example. Staff were storing login credentials in a slack pinned message because using the right tools were a headache.
    • alibarber 6y ago
      One thing I despise is internal systems with self signed certs because setting it up properly is a faff or no one can agree on the latest and greatest way to do it. Oh cool that’s fine I’ll just click away all the big scary warnings in my browser to access this page. I’m an engineer and know what I’m doing! It’s a super strong key anyway. Oh wait I’ll just send this link to Bob in accounting and tell him to do the very thing we’ve been telling users not to do under pain of ridicule for ages and then he’s now doing that 10 times a day and now all of https is pointless because he knows that ‘it’s probably fine to ignore it because I have to do that at work’...
      • outworlder 6y ago
        I have tried (unsuccessfully) to argue this point at a previous employer. Email server certificate expired and IT sent messages teaching people to ignore cert validation errors.
      • baobabKoodaa 6y ago
        Part of the blame here should go to web browser developers. Self signed certificates pop up a huge warning while plaintext http connections do not, even though the former is more secure than the latter.
• dr-detroit 6y ago
  Where I work I am not allowed to make risk decisions for the organization.
• corytheboyd 6y ago
  Please do not use random variable names in source code. Uglify/minify instead. It’s a bit unclear because right above that “tip” is obfuscating code, did I miss something?
  • Shared404 6y ago
    For JS, does it not make sense to use random variable names in production? Obviously you don't want to while developing, but it seems like an efficient method to help obfuscate.
    • umvi 6y ago
      Yeah, GP is saying you as the developer should not use random variable names. Let an uglifier select random names for you.
      • Shared404 6y ago
        Ok, that makes sense. Thanks for clarifying for my stupid self.
  • GiantSully 6y ago
    Guess obfuscation is the goal, and the methods include using random variables, disordering code, inserting verbose code...
• codingdave 6y ago
  The higher level of abstraction behind an article like this is that security is a mitigation activity within a broader risk management plan. Most of the time, the best practices in the security field are best practices for good reasons - they costs are a reasonable to mitigate the business risk of not having security, so we do them. But there are times when you just need to discourage people, not truly secure a site. Not many, but they do exist. Pseudo-security in those cases is cheap and meets the business needs. Likewise, there are times when best practices aren't good enough, and you need to go beyond the norm. Either extreme is driven by thinking through the acceptable risks, evaluating costs, and making a decision.
• dec0dedab0de 6y ago
  I'm surprised port knocking never really caught on. Does anyone know of it being used in production anywhere?
  • weare138 6y ago
    I'm guess because VPN's and SSH became so ubiquitous? Having a single point of entry, especially when combined with 2FA, is probably good enough for most situations.
  • e12e 6y ago
    It's generally more convoluted than the equivalent alternatives, with less features. You need a shared secret - you could use totp - or you could use vpn/ssh with key based auth - both offer authentication of/to both sides and encryption/confidentiality. Blocking all icmp traffic breaks tcp - so true "invisibility" isn't that grät either.
  • wrnr 6y ago
    I can neither confirm nor deny
  • DiffEq 6y ago
    Well kind in the theme of port knocking Postfix has a Grey Listing option which kind of works like that for spam though not the same thing.
  • jonfw 6y ago
    port knocking is just, another way of doing a password, right? It's pretty much just a PIN code with a slightly obscure method of inputting the digits. I would imagine that this is open for a man in the middle attack- if this traffic were intercepted- you'd be able to see port numbers, right?
    • outworlder 6y ago
      Well, yes. But where would the attacker be if they are in a position to intercept the traffic? The answer to that may dictate if the technique would have value for you.
• VonGuard 6y ago
  I had a Mac SE with an ethernet card in 2001, around when Red Worm was loose. We put an HTTPd server on it, and watched as each RedWorm attempt came in. This ancient super slow machine not only stayed completely safe despite being on Mac OS 7.5 or something around there, while Windows machines of current vintage were being taken apart around the world. Added bonus, the slow speed of the SE meant it took about 10 times longer for each Red Worm attempt to give up, so we at least monopolized some tiny portion of those infected systems for a bit, keeping them from infesting others for a few more seconds...
  • jlgaddis 6y ago
    In case anyone else is confused at first, I'm assuming you meant s/Red Worm/Code Red/g
• ricardo81 6y ago
  I've used some very tight-arsed VPS providers at the low range (128MB/1IPV4/$12 a year) and some of them mention a high load, and it's mainly due to brute force on port 22. It makes sense to change port purely to avoid the low-barrier noise but of course it isn't much better security. Port knocking is on the same lines. I'm by no means a security expert but these measures would surely help: less opportunists = less opportunities. Saying that, I'm public key auth only and disabling any public facing service I'm not using. The "security through obscurity" thing seems like a warning to avoid shortcuts rather than some implementations that help reduce noise. As long as you understand the fundamental problem of security, the obscurity thing is just a sidebar.
  • mywittyname 6y ago
    > less opportunists = less opportunities. You miss 100% of the shots you don't take applies to hackers as well.
• tyingq 6y ago
  Moving sshd to a non-standard port is certainly a good example. If only because it turns down the log noise. So that an "unauthorized connection" stands out.
• DiffEq 6y ago
  I think that most initially looked down on the security through obscurity layer as flawed only because many people, a few years ago, thought that this is the only layer they needed. Somehow over time many people began to think that this layer is not useful at all. A little bit of thinking about the issue would absolve one of the approach to completely exclude that layer. Also it is so easy and cheap to implement is another reason to discard it because in many organizations today people think that security can only be had by spending boatloads of money on people and software. Surely a simple, fast and cheap solution can't really reduce risk now can it? And then on top of those things people do not think about, nor fully understand risk, hence the whole Covid 19 scare and the many other things in the world people are afraid of.
• cataflam 6y ago
  Agree with the article. People have been misinterpreting "security by obscurity is bad" to mean any obscurity and obfuscation is bad. Instead it was originally meant as "if your only security is obscurity, it's bad". Many serious real-world scenarios do use obscurity as an additional layer. If only because sometimes, you know that a dedicated attacker will be able to breach, what you are looking for is to delay them as much as possible, and make a successful attack take enough time that it's not relevant anymore when it's broken.
  • KarlKode 6y ago
    An argument against obscurity is that it adds additional pains for your "regular" users (as in developers/3rd party developers/app developers) while being a small deterrent against unauthorised users (as they will be able to circumvent the "obscurity layer" and replicate their method to other bad actors). edit: In the first sentence "against" is not what I wanted to say: what I wanted to say is that it "downgrades it's effectiveness". I agree that obscurity can and sometimes should be a layer of security.
    • PragmaticPulp 6y ago
      > An argument against obscurity is that it adds additional pains for your "regular" users (as in developers/3rd party developers/app developers) No one should be applying obscurity to public-facing APIs or anything for which documentation is widely distributed outside the company. A better example would be Snapchat's intense and always evolving obfuscation strategies: https://hot3eed.github.io/snap_part1_obfuscations.html https://hot3eed.github.io/snap_part1_obfuscations.html Even though someone took the challenge to de-obfuscate most (but not all) of the protections, just look at how much effort is required for anyone else to even follow that work. More importantly, consider how much effort is required relative to other platforms. It's enough of a pain that spammers and abusers are likely to choose other platforms to attack.
      • gowld 6y ago
        When security is totally impossible because there is no way to distinguish a trusted party from an adversary, obscurity is the only hope.
• 3pt14159 6y ago
  In DC there is this concept of "the blob" which is basically shorthand for "The Washington consensus that isn't verifiable, but that most people parrot since to hold an opposing view doesn't really get you anything because even if you're right, nobody will remember. All that they'll remember is that you're that weird guy that looks at stuff with a strange perspective and that you may be too dense to social signal that you're in the blob." I've noticed the same thing with software developers. - "Client side encryption in JavaScript is useless!" Until CloudBleed came out and the only company that was safe was a password manager that used it. To thwart client side encryption you need to actually modify the contents of the JS payload, which is detectable. But no matter how much evidence I give that this tactic works and is actually used in production and that it actually stops attacks, programmers just don't care. - "Don't do security by obscurity!" But then we all implement passwords (which is just security by obscurity) and the best people in intelligence don't have LinkedIn accounts. Anyone can join an OSINT forum and see the actual tools that get used. Security by obscurity works for many, many actors. There are many, many little bits of stuff like this. Think to yourself: How many times has code that you've written lead to an RCE vuln that was exploited. Personally, I can only give a lower bound, and that lower bound is zero because I'm extremely careful, but I don't pretend that it's never happened. Anyone that is familiar with data science or economics or political economy understands that when a signal is dampened the response is dampened.
  • Spivak 6y ago
    > "Don't do security by obscurity!" But then we all implement passwords (which is just security by obscurity) Thank you for being someone else who recognizes this. If having a secret piece of knowledge grants you access to the system then it's obscurity. Once we admit that then we can start talking about the difficulty of guessing that knowledge as the actual important factor.
    • jlgaddis 6y ago
      > If having a [password] grants you access to the system then it's obscurity. Perhaps if you're hiding it under the doormat in front of the door and expecting it won't be found. Or writing your PIN on your ATM card with a sharpie and leaving it on the dash of your car with the doors unlocked and your windows down. In most cases, however, it's part of an overall system that involves authentication, authorization, and (hopefully!) accounting to protect access to resources.
• jchook 6y ago
  Ultimately if governments (such as Australia, US) continue to prevent citizens from using encryption, we will have no choice but to employ security-by-obscurity atop secure-by-design principles to have privacy. For example, making ciphertext look like cleartext[1], or hiding text in images[2]. 1. https://steganography.live/ https://steganography.live/ 2. https://github.com/DimitarPetrov/stegify https://github.com/DimitarPetrov/stegify
• transpute 6y ago
  Obscurity has been used for detection of bots engaged in profitable ad fraud, by having web clients execute a JS payload whose behavior can be profiled. Temporary payload obscurity enables a silent alarm, which can be used to stop financial payouts. Unlike many approaches to cybercrime defense, obscurity-enhanced bot detection has lead to both prosecution and extradition of accused attackers, https://www.cyberscoop.com/tag/methbot/ https://www.cyberscoop.com/tag/methbot/ White Ops technical talk at PSEC18, https://youtube.com/watch?v=Aqdn09myGlM https://youtube.com/watch?v=Aqdn09myGlM
• JshWright 6y ago
  There is a reason the military doesn't paint their tanks bright pink... Armor is important, but if you don't get shot at in the first place, even better.
  • spicybright 6y ago
    I like this analogy!
  • 4ad 6y ago
    Security by obscurity is not painting tanks in camo. Security by obscurity is assuming your enemy won't find your tanks because you didn't broadcast on public radio where your tanks are.
    • JshWright 6y ago
      That is another appropriate analogy (and it's why the military invests in SIGINT). To the point though, no one should "assume the tanks won't be found", but it's still worthwhile to do things to make it less likely they will be found.
  • omginternets 6y ago
    In military parlance, this is the distinguish between cover and concealment. In practice, good cover often provides some degree of concealment, but on a purely theoretical level, the two are orthogonal.
• cosmotic 6y ago
  Intentional obscurity needs to be identified as such so maintainers know what follows isn't actual security. Obscurity also clouds maintainability, often making things difficult to diagnose and debug.
• vsareto 6y ago
  >However, if you can reduce the risk with zero cost, you should do that. Zero cost is rarely, rarely true with regards to operations. If you use non-standard ports, you'll have to document that somewhere, or else it becomes tribal knowledge. If you don't document it, and someone leaves, how do you know how to access your servers? At the very moment you don't know how to SSH in, you've just paid the price. It's no longer zero cost. If you do document it, you must now take the time to manage the permissions to that document, figure out who needs to know, and then change access as people come and go. All of that requires time, which also has a cost. Plus all of this also has training costs when you onboard new people. Zero cost is a real thing with computer science but not operations.
  • derefr 6y ago
    Zero net cost is certainly almost never a thing; but zero incremental cost is often a thing. To further your alternate-port example: let's say you have some instances running on Google Cloud. GCP already has a big CLI codebase that they get everybody to use, which has a command `gcloud compute ssh` for connecting to instances, which already has tons of magic built into it. It would therefore be pretty easy for GCP to add additional magic — e.g. randomizing the SSH ports of newly-deployed instances, and then publishing those ports as project secrets in a way that the gcloud CLI tool can discover and use in the `gcloud compute ssh` subcommand. The incremental cost of an approach like this is effectively zero: the DevOps folks didn’t have to build anything new to get this advantage, because they already built all the infrastructure required (i.e. spent the labor-cost you’d be spending) in the process of getting some other, earlier advantages. In a sense, setting up a platform or infrastructure that's more complex/flexible than what you require at the time, is the opposite of "technical debt." Rather than saving labor now but needing to be paid down with later labor, it requires more labor now, but potentially saves labor later. It’s a bit like paying a retainer fee: you get less than you pay for (or nothing) up front; but in return, you get things "for free" later on. "Tech equity" might be a good term for this — it's what you get when you invest labor into your tech stack.
    • vsareto 6y ago
      I don't disagree, but this kind of goal post moving is how zero cost will turn into a buzzword down the line because it'll really mean zero incremental costs when referring to operations. Plus, zero incremental costs may only apply if you match the situation being presented. If not, you may have real costs associated with implementing obscurity. This evaluation of whether you will get zero incremental costs or not is a cost in itself. It's just a misappropriation of the term from zero cost abstractions and it bugs me, especially since it's being ported from compiler theory/engineering to operations, two things which rarely have anything to do with one-another. They'd be way better off coming up with "cost-effective obscurity" ideas, instead of calling this zero cost.
• xfz 6y ago
  Good, thought-provoking article, but use with caution. I've seen security through obscurity misused too often as the only line of defence, or as a "temporary" stop-gap that outlives its usefulness. It can lead to a false sense of security. Such measures also do not tend to keep up with changes as attacks become more sophisticated or cheaper to carry out. You also need to make sure that there are no unintended consequences - does your non-standard configuration make it harder to apply upgrades? Does your own penetration testing also scan all ports, or is it only going to discover weak servers running on port 22 on your network? That said, I would do the type of things mentioned in the article as an "added bonus", but try to exclude them from my overall security evaluation (either rough mental model or formal threat model).
  • 2ion 6y ago
    > I've seen security through obscurity misused too often as the only line of defence, or as a "temporary" stop-gap that outlives its usefulness. It can lead to a false sense of security. Exactly. > we need for some reason make this development-stage service publicly available on the internet, and it's connected to a lot of our services internally, but we can implement AAA only later and we need it now. No issue publishing it on an obscure route/IP/domain name? And the setup stays online for 5 years.
• darkerside 6y ago
  Shhh not if you keep telling people about it!
• tptacek 6y ago
  There's something to the idea of rehabilitating "obscurity", or at least recognizing that "cost" is part of threat models, and you can raise costs for particular attack vectors by degrees instead of "to infinity". But SSH is a terrible example, because the cost to the defender of simply not having SSH vulnerabilities is the same, or even less, than the cost of obfuscating it with nonstandard ports, "port knocking", or fail2ban, which are all silly ideas. Just use SSH keys, and disable passwords. I think maybe it comes down to this: dialing attacker costs up incrementally can make sense if it's the most cost-effective way for a fully-informed defender to improve security. But incremental cost-increasing countermeasures aren't a substitute for sound engineering; you don't get to count "having to learn stuff" as a valid defender cost.
  • MiroF 6y ago
    The cost of not having SSH vulnerabilities is infinite because there is no way to ensure that.
  • deleted 6y ago
    [deleted]
  • meowface 6y ago
    It's not really a direct security advantage, so this is mostly off-topic, but changing the default port does greatly reduce log noise, and theoretically could be a bit less taxing for your network connection or CPU if it's a cheap server not intended for publicly hosting services. (If it is then the traffic would be a drop in the bucket compared to regular production traffic, though. And it's admittedly probably a drop in the bucket either way.) Reducing log clutter alone probably does confer some small indirect benefit, since it's less likely a more sophisticated attempt or successful breach would go unnoticed when inspecting logs. (Assuming there's some SIEM log forwarding or that it's not a situation where an attacker was able to or wise enough to wipe logs.)
  • xioxox 6y ago
    One advantage of putting ssh on a non-standard port is that your logs, which are otherwise filled with automated ssh break-in attempts, now become almost empty. It's much easier to look for other problems when the signal to noise is increased.
• goalieca 6y ago
  Security by obscurity has a bad reputation because it should never be used in place of a proper secure solution whenever possible. Most security experts will argue in adding layers of defence where the proper solution is not possible. There are other considerations for obfuscation as well. A risks assessment might consider the skill of the attacker and the resources required (eg: computational power) in order to break in.
• fooblat 6y ago
  To me this seems like a bit of a strawman argument. The claim was never that using obscurity is bad and should be avoided. As I first heard it, "Security through obscurity is not security" is saying that if you are relying on obscurity to keep your stuff secure then you aren't doing enough. I think this is still true and the conclusion of the article agrees Security by obscurity is not enough by itself. You should always enforce the best practices.
  • daitangio 6y ago
    I agree. Obscurity is a weak strategy. If you can make obscurity not necessary you will gain far better results.
    • daneel_w 6y ago
      It's not a strategy. It's a tactic. And as many others in this discussion have pointed out, people who recommend to use obscurity never tell others to let their whole security strategy hinge on it. It's just a useful tool; a tactic.
  • formerly_proven 6y ago
    > The claim was never that using obscurity is bad and should be avoided. Yet. All of these are from HN. > 3. Since when is obscurity a valid security measure? > Security through obscurity, not a valid security plan. > The problem with these "obscurity as a valid security layer" arguments is that there's already obscurity built into these protocols. > Especially since most people believe "Obscurity" to still be a valid security technique. > You're just reciting the same tired old rhetoric that security through obscurity is a valid defense mechanism. It's just not. > I thought the general consensus here is that security by obscurity is bad. > Obscurity is bad because it makes you _think_ it adds security. > To maybe give some perspective _why_ security people say that security by obscurity is bad - and especially serving ssh via port 64323: [...] > I dismissed it as security through (bad) obscurity but is there a valid security reason to do this? > Compression is not encryption and security by obscurity is bad practice. > it's understood that security by obscurity is bad. > Security by obscurity is bad, of course, but in that model it's such a minor factor. And countless many more. Some of these reference "security by obscurity", which, if you're kind, you can interpret as "security only through obscurity" (though reading in context this mostly doesn't seem to be what is meant), while others dismiss obscurity entirely. You will also regularly find commenters lament this point of view as the "mainstream idiocy".
• blakesterz 6y ago
  I was thinking maybe this goes back to people in security looking at things in a different way than others? Like ITSec folks spend all day everyday reading about every possible way a bad actor can make bad things happen. They look at something like changing the port SSH listens on and think about all the ways the best & brightest bad actors will get around that in no time at all. Everything ends up looking pretty useless at some point, because you end up seeing that it's possible to get around nearly everything. Another example might be folks in the security community saying that SMS 2fa is no good because all it takes is someone taking over your phone account to get around. Sure, that happens, but not all that often, and usually happens to people with something that's worth time & focus by talented bad actors. "Security by obscurity is not enough by itself. You should always enforce the best practices. However, if you can reduce the risk with zero cost, you should do that. Obscurity is a good layer of security." I rather like the conclusion.
• abhishekjha 6y ago
  This came up in the stackoverflow podcast where Reddit founders were the guest. They mentioned that they stored plain text passwords initially which is fundamentally a bad design but at the same time it helps to block spam. If a user starts to create a lot of accounts programmatically they generally use the same password thus much easier to filter. Security via Obscurity, if you can do it, can be very very effective.
  • tgb 6y ago
    You could do that without a plain-text password, though with a salt it would be harder (though you could still do it proactively by checking the password when the account is made).
    • abhishekjha 6y ago
      Yes, there was an ongoing criticism from Joel regarding storing plain text passwords.
    • tzs 6y ago
      To check the new account's password at creation time against existing salted hashes, you'd have to hash the new password with each existing password's salt. If you are using something like bcrypt or scrypt which is designed to be slow at this, that might take a while if you have a lot of existing accounts. Maybe a Bloom filter approach? Besides the salted slow hash you store of each password, also put the password in a Bloom filter. Check new passwords against the Bloom filter. You'll get some false positives that way, but maybe that is acceptable. I'm seriously tempted, if I ever have to implement a password system again, to allow up to 256 characters, just store an unsalted SHA256 hash, and tell people on signup that they should be using a password manager with a long random password if they care about security of their account.
  • salamander014 6y ago
    It's possible to track similar passwords in a safe way over a short amount of time. Keeping any user's password or any security token in plaintext is just disgusting. Regular people have a hard enough time navigating the digital world without needing to worry about whether their credentials are safe. Anyone who stores passwords in plaintext is disgusting and should not be managing digital services. Period. This is how breaches happen, and it should be a fine-able offense.
• afrcnc 6y ago
  So the "developer" who created an "educational" ransomware project that was abused for half a decade by criminal groups now has a controversial and low-level view of security practices and is broadcasting it to the world. I'm shocked, I tell you. Shocked!
• shmerl 6y ago
  Obscurity is double sided. While the attacker can be hindered by it, so is someone who can audit the defense and find its deficiencies. I always thought that was the main argument for avoiding security by obscurity - the benefit of better audit and improving defense overall outweighs the benefit of obscuring it.
• daenz 6y ago
  No mention of port knocking for SSH. I used to be scanned constantly for SSH logins. So I changed the port. The login attempts stopped for awhile, but eventually they found the port. Now with port knocking, I haven't seen a single attempt. Security by obscurity alone is bad, but as another layer, it can be great.
  • Majromax 6y ago
    > Security by obscurity alone is bad, but as another layer, it can be great. I beg to differ in your case. Had you left SSH on its default port, what would your expected time-to-compromise be? Presumably you weren't using a root:password credential, or else your system would not have remained up enough long enough for you to implement any obscurity. But if an attacker, with full ability to try logins, could not reasonably guess your login credential in the lifetime of the universe (i.e. public key SSH or a strong password), then you've not improved security by moving to a port-knocking model. You have reduced nuisance, but nuisance isn't part of the standard threat model for SSH security. To put it another way: you've not seen another unauthorized login attempt, but would you be comfortable relying on that and use root:password as your access credential?
    • daenz 6y ago
      I disagree. Suppose the latest SSH has a 0-day, now I am vulnerable, even though I only use PK-auth. Obscurity is just another layer, and the purpose of layers is to help make rare vulnerabilities (like 0-days) not compromise the system. By hiding the door, they cannot even touch the 0-day without another rare vulnerability.
  • MaxBarraclough 6y ago
    If you don't need to support access from arbitrary IPs, IP whitelisting is another good additional layer over SSH. Keeps the SSH scanners out, and also significantly raises the bar for a determined attacker.
• _tk_ 6y ago
  To maybe give some perspective _why_ security people say that security by obscurity is bad - and especially serving ssh via port 64323: Typically you want to know who is connecting to what server via what service and log these connections. If something is off, an alert can be generated. If ssh isn't served on a standardized port, logging and alerting becomes more complicated - albeit not impossible. There is more housekeeping to do. In case of a handoff, things like this need to be documented. If all services work on their default port, there is no need for documenting them. In the case of compromise, it becomes very hard to identify how a machine got compromised. Yes, a lot of people do not do a full port scan. But those are not the people exploiting risky vulnerabilities. Security by obscurity reduces your risk, but only to a certain extent. Having a proper patch management or firewall management in place reduces your risk a lot more. A lot of owls do get killed by humans, despite their camouflage.
  • mercer 6y ago
    > Typically you want to know who is connecting to what server via what service and log these connections. If something is off, an alert can be generated. If ssh isn't served on a standardized port, logging and alerting becomes more complicated - albeit not impossible. Could you elaborate on that? I serve ssh on a non-standard port precisely in part because it drastically cut down on the noise of failed log-ins, to the point where when I check the logs I'm almost the only one who actually bothers to try to log in via that port. That seems like a win to me.
    • thinkharderdev 6y ago
      Not the OP but I assume what they mean is that if you have network-wide monitoring across a network with lots of servers then it won't be able to easily make sense of what is happening if servers are all using non-standard ports for things.
      • _tk_ 6y ago
        Correct. This is an argument made from a corporate network perspective.
• deleted 6y ago
  [deleted]
• burtonator 6y ago
  I mean crypto is based on security by obscurity if you think about it. It's just REALLY obscure. You can technically compute the private key for someone's Bitcoin wallet for example. It's just you'd hit the end of the heat death of the universe by then.
• calvinmorrison 6y ago
  Security by Obscurity is great. This is a takeaway from the port knocking conversation here last week. If there's a zero day exploit in sshd, I'd rather it be behind some layer you would have to "know" to get in, rather than sitting open to the world. Why make your target bigger than it needs to be?
• GhostVII 6y ago
  One thing I didn't see discussed in the article was the balance between the benefits of security by obscurity, and the benefits of having your code open source (or at least making your security methods known) so more people can audit it. Personally I don't actually think there is that much security benefit to having open source code since most people don't audit random codebases for fun, but that is one of the arguments I've heard against obscurity. Of course some methods of obscurity can still be done with open source code as well.
  • topkai22 6y ago
    Open sourcing has to be done with the audience in mind. It generally doesn’t make sense to (publicly) open source a system that is idiosyncratic to a single organization. The only likely interested audience is hostile attackers. A useful general purpose dev tool though? Sure, and the people using it might be able to help.
• terlisimo 6y ago
  Arguably, most security is security through obscurity. No password -> simple password -> complex password Plaintext -> Caesar cypher -> Vernier cypher -> modern cyphers 40-bit crypto -> 56-bit crypto -> 128-bit crypto -> 256-bit crypto 0.0.0.0 network allow-list -> /24 network allow-list -> /32 (per host) network allow-list allow by default -> deny by default standard port -> non-standard port We just add layers of obscurity until they add up to "enough" and don't grow into "beyond tedious".
  • saagarjha 6y ago
    Passwords and keys are not "obscurity", they are mathematically difficult to break if done correctly. There is no mathematical guarantee for security by obscurity.
  • LordOfLamers 6y ago
    In fact, there may be obscurity in the encryption method. You won't find a decryption method for my encryption algorithm on the internet. You have to do crypto analysis. My algorithm is reorganized caesar with block encryption
• n0on3 6y ago
  It seems to me that the article is missing a few of points on what "security by obscurity" means. From Wikipedia: "reliance [...] on design or implementation secrecy as _the main method_ of providing security [...]" So, to use the model mentioned in the article, a single slice of cheese. It's not "an additional layer of defense", it's the main one (so you have other... weaker layers? ¯\_(ツ)_/¯) Second, "reliance on secrecy of design and implementation" is different from "reliance on secrecy of _whatever-else_", because design and implementation are most often either easily discoverable (sure, occasional skids might not scan port 64323 but what about someone who can observe your traffic?) or pretty much guaranteed to be discovered by adveraries with (not even as much as one might think) time and motivation. Third, some of the examples mentioned (e.g., the decoy cars) are not even security by obscurity, that's called deception. So, sure, you can do non-standard stuff to make it harder for _some_ not discover your vulnerabilities (ssh non-standard port is actually a good thing given the massive amounts of bots around), but that should never be your only (or your main) layer of defense. Security by obscurity is not underrated, by definition it's just bad.
  • jjeaff 6y ago
    I agree with your understanding of security by obscurity. But I think the popular understanding has started to be more along the lines that the author counters. That if any security measure is "obscurity" then don't do it, it's bad.
    • wintermute_ 6y ago
      This is the problem with "sound bite" bits of conventional wisdom. The more it's used and misused, the less it's actually understood. People hear "Security through obscurity is bad" and just interpret those words however they want without listening to the rest of the actual advice being given. It's not to never use obscurity to your advantage. It's that you need to be aware (and far too many weren't at one time) that you cannot rely on obscurity as a form of defense. If I have an old, buggy unpatched version of an admin page sitting on an obscure random URL, but I decide I don't need to bother patching it because eh, it works and it's too much effort to patch and what are the odds someone will guess my super secret random URL, then I need to think about why "security through obscurity" is bad. And that false sense of security is why they say security through obscurity can be worse than no security at all. They key is to promote vigilance and actual hardening of systems and not expend precious time devising ever more elaborate obscurity hoops that cost you more than they cost an attacker in time and effort to defeat, and are in the end ineffective. That's not to say you should leave ssh listening on port 22, you really shouldn't. It's like the difference between leaving your front door unlocked and leaving it unlocked and putting up a big neon "Open 24 Hours!" sign in the window.
• gumby 6y ago
  By definition cryptography is security through obscurity as you map something from a small space into a large space (e.g. multiplying Two numbers you know is easy while finding two prime factors is hard). The aphorism is unfortunately too short to be enlightening except to someone who already understands it.
• hatch_q 6y ago
  Blog seems to ignore the fact that password is just security by obscurity. And having absolutely no obscurity with security is very hard.
• drewg123 6y ago
  Almost 2 decades ago, I maintained our company's self-hosted web server on FreeBSD/alpha. It ran a simple (thttpd) web sever. I remember looking through the logs, and seeing script-kiddie attack after attack fail due to running thttpd instead of apache, FreeBSD rather than Linux, and alpha rather than x86. I obviously kept the machine patched and up-to-date, but I think I probably could have left it unpatched, and it still would have been fine.
• blamestross 6y ago
  Avoiding "Security through Obscurity" is not about how useful it is. It is about keeping security experts and cryptographers alive and out of prison.
• OminousWeapons 6y ago
  The article is correct but they miss the true value add of security through obscurity: signaling lower ROI to attackers. Security through obscurity generally forces attackers to perform more actions and do more recon. Every additional action taken increases the risk of detection by defenders, costs the attackers valuable time (meaning lower ROI), and makes the target less appealing relative to other targets. Security through obscurity tactics are absolutely useful tools in a defender's toolbox (in conjunction with other security countermeasures).
  • thinkharderdev 6y ago
    I think it depends on what system you are talking about and where it is. So if you have an internet-facing server running sshd on port 22 then you are going to get hammered with low-effort, automated scans and changing to non-standard port can cut down on noise and at least "hides" you from low-effort attackers. But if your server is in a hardened, private subnet then any attacker that is even in a position to connect port 22 has already bypassed multiple layers of security and is already invested so likely won't be in the least bit deterred by a non-standard port.
  • nobody9999 6y ago
    >The article is correct but they miss the true value add of security through obscurity: signaling lower ROI to attackers. Security through obscurity generally forces attackers to perform more actions and do more recon. Exactly. I came here to say much the same thing, except with a non-digital analogy. I live in a (relatively) small apartment building with five floors and four apartments on each floor. I live on a floor that isn't the top or the bottom floor. That reduces the likelihood that someone who opportunistically gains access to the building entrance or the roof will attempt to access my apartment. What's more, unless I'm being specifically targeted (which obviates any sort of obscurity argument, given that specific focus is given to a target rather than a service exposed by many), it's pretty unlikely that my apartment will be robbed since there are other, much more accessible apartments than mine. That's the "security through obscurity" bit, which has a measurable, positive impact on the security of my home and belongings. However, that doesn't mean locking my door is inappropriate or overkill. In fact, if I am being specifically targeted, locking my door is likely not sufficient either, as an intruder could bash down my door or drill out the locks to gain entry. I suppose I could install surveillance cameras focused on my front door (as well as inside my apartment), allowing me to identify intruders after the fact. And I could install safes to hold my valuables as well. Each of those security precautions have some positive value, and absolutely contribute to the idea of "defense-in-depth". That said, there is a real trade-off between increased security, cost and usability. While the relative "obscurity" of my apartment confers some security value, it's not nearly enough to stop someone from trying all the doors in the building, so I lock my door. I don't, however, have safes in my home or surveillance cameras outside the door and in every room, as that (unless I'm being specifically targeted) doesn't add enough value to justify the cost of such measures. Which brings us to the point of security -- which is to protect assets. However, if the cost expended (in resources and usability) is greater than the value of the asset(s) being protected, it doesn't make sense to do so. Security through obscurity can (but doesn't always) provide a modicum of value, but isn't a complete solution itself. Used in conjunction with other, reasonable (in the context of cost vs. value being protected) measures, it can be a valuable tool.
• filleokus 6y ago
  My beard is not grey enough to know about how the Security by Obscurity meme/mantra have evolved in the tech community. But one thought I have is that this more nuanced picture is much more complicated to tell beginners. Beginners / not as security conscious developers often, wrongly, assume that obfuscation is much more powerful than it is. The safest digest of the "Apply ≈Kerckhoff's principle, but some obscurity on top of that is not a bad idea if it's cheap to implment", is probably "security by obscurity is bad!1!". Certificate pinning or sandboxing in mobile apps won't stop people from reverse engineering your API's. But if your personal belief is that it's like almost a state actor level attack to see your API routes or modify requests, it will undoubtedly influence how you implement them. I've seen some serious problems where companies do really bad things (like sending the ID of the currently logged in user and not checking it server side, allowing for execution as arbitrary user), which I guess at least partly arose from thinking along the lines of "It's only our signed code that will ever make these requests". Even bad developers wouldn't make the same misstakes in ≈2020 on the web, where the understanding that the client is untrustworthy have fully statured the common understanding.
• jkire 6y ago
  To me all these slogans around security is to ensure people really, truly, actually think about things before they go against the grain. Is using obscurity as part of your defence always wrong? No, but equally it often adds a false sense of security. Popularising these easy to remember slogans helps change peoples defaults. Nowadays, if someone sees an attempt at security by obscurity it (hopefully) rings alarm bells and causes them to interrogate it to ensure that there is also other security measures in place, or that it is otherwise OK. It's the same with "never roll your own crypto" I find it somewhat interesting that the article uses an example which falls right into another pitfall that "security vs obscurity" is trying to prevent. > SSH runs in port 64323 and my credentials are utku:123456. What is the likelihood of being compromised? > > Now we changed the default port number. Does it help? Firstly, we’ve eliminated the global brute forcers again since they scan only the common ports. ... So, if you switch your port from 22 to 64323, you will eliminate some of them. You will reduce the likelihood and risk. This is technically correct. However, the author has identified a security concern that he wants to mitigate: brute force attacks. Now, you could try and reduce that risk by using a different port which might reduce it by 50%, or* you could fix this issue by deploying fail2ban (or using ssh keys, or VPNs and bastion boxes, etc), and thus negating that attack vector entirely. There isn't even a usability argument here: making people remember the right port for ssh is less usable than setting up fail2ban. Of course there are tonnes of other attack vectors to consider, but in general where possible its better to "properly" (fsvo.) mitigate those concerns and only rely on obscurity where that isn't possible. If a concern is mitigated than adding obscurity does almost nothing, while likely proving to be more annoying to the end user (like in the case of specifying a port in the above example). Now of course that's not to say that you should never use obscurity, but if you do then I think its entirely reasonable that you are prepared to give a good justification why its appropriate. For example, sharing via secret URLs is a good example where it can be easy to justify in some settings, but it equally may not be OK for documents that are really really sensitive as its relatively easy for links to be shared in error with the wrong people. RE some comments about using obscurity to signal that your deployments would be harder to get into and thus for attackers to not bother: I'd genuinely love to know if that is true or not, I wouldn't be surprised if attackers assumed obfuscation mean that the more advance security measures hadn't been deployed (otherwise why bother with obfuscation?). * Based on the twitter poll in TFA, though if you have a targeted attack it seems sensible to assume that if port 22 doesn't work they'd try again with other methods
• miles 6y ago
  Changing SSH port is far more efficacious at reducing nonsense than the Twitter poll in the article suggests: > "I ran an experiment with a virtual machine exposed to the internet which had sshd listening on port 22. The server stayed online for one week and then I changed the ssh port to 222. The number of attacks dropped by 98%. Even though this is solely empirical evidence, it’s clear that moving off the standard ssh port reduces your server’s profile."[0] > "In the time that I gathered 7,025 connection attempts to my SSH daemon on port 22 I received 3 on port 24."[1] Also, great top comment by 16s[2] in this HN thread, "Why putting SSH on another port than 22 is bad idea".[3] [0] https://major.io/2013/05/14/changing-your-ssh-servers-port-from-the-default-is-it-worth-it/ https://major.io/2013/05/14/changing-your-ssh-servers-port-f... [1] https://danielmiessler.com/blog/security-and-obscurity-does-changing-your-ssh-port-lower-your-risk/ https://danielmiessler.com/blog/security-and-obscurity-does-... [2] https://news.ycombinator.com/item?id=6615994 https://news.ycombinator.com/item?id=6615994 [3] https://news.ycombinator.com/item?id=6615734 https://news.ycombinator.com/item?id=6615734
  • rjkennedy98 6y ago
    It's also way less effective than they mentioned because they didn't get hacked either way. So there was 0% difference in effectiveness between port 24 and 22 since the ssh was properly configured. Security by obscurity only matters if you aren't secure in the first place. It can be a good extra layer of protection, but the worst examples of security mishaps I've seen are because people find the security unnecessarily burdensome and so they bypass it entirely. So in that way obscurity in that case has a real cost.
    • 10000truths 6y ago
      Even unsuccessful SSH attempts can have operational costs, though. The machine still accepts the TCP connection and does the SSH handshake. If I’m running a server and I’m billed by data usage or by vCPU minutes, I don’t want to waste my allotted resources by making it easy for every half-baked crawler around the world to make connections to my machine. Using a non-default port cuts down those numbers significantly. Sure, a targeted attack won’t be thwarted, but at least the server is not being DDoS’ed anymore.
• JackC 6y ago
  The way I think about this, there are some aphorisms that work as actual design principles, and some that are just used to defend a decision you have already made to someone who doesn't need to understand it. "There's no such thing as security through obscurity" is an example of the second; you can use it to mean "shut up and stop asking questions about the secure system I designed," but you can't use it to design a secure system or explain why your choices are correct. The useful design principles behind "no security through obscurity" are just a little more complicated -- they're more like "every secure system must have defined entropy sources (such as keys) that provide a lower bound on the security budget against a hypothetical attacker with knowledge of everything except for the entropy sources." And, "because obscurity does not measurably improve the lower bound on the security budget, it is only a good idea if it also does not raise the chance of implementation errors, does not make it harder to obtain third party reviews of the system, and does not make the security of the system harder to prove." An argument about whether something is security-through-obscurity-in-a-bad-way probably actually wants to be an argument about an underlying design principle along those lines. I don't exactly begrudge people using "shut up and trust me" phrases in situations where that's needed, but I think they're almost always unhelpful in forums like this.
  • reagent_finder 6y ago
    I was going to make approximately this point. However, I think it's also important to have some of those "shut up and trust me" phrases codified and have them available for the layman via Google. Because sometimes those people demand "proof" or they'll go searching for it themselves and if it's right there to be found and most major sources agree... well, the discussion can then be "Is this just obscurity where security is needed?" AS IT SHOULD BE. If you get right down to it, passwords are just obscurity. Usernames are just obscurity. In this very thread people are dismissing port knocking while it's functionally equivalent to a password. I will personally stand by "security through obscurity is not security" forever because that way we can get to the actually interesting question -- what level is needed for this service? Let's take a simple example from the public Internet -- you want to share something. So you put it on a server with Apache. You add TLS and PFS. You hide it in a folder structure somewhere. You add a single-use token or just htaccess. Any of those individually would be obscurity, but put together they are most likely more than enough for... well, anyone. So is it still obscurity or actual security? That's a debate for the ages, but I think most people would agree all of those put together are fine-ish, but pick just one method and it's just obscurity. This whole thread is basically just a philosophical debate where half the people haven't read the article, the other half disagrees with minutiae in the article, the third half disagrees with major points of the article, the 4th half is sharing anecdotes and the 5th half just wants to participate.
• Naac 6y ago
  Agree with most people here that security by obscurity is bad "by itself". For example, changing your public server ssh port from 22, to say, 2942, is a great way to limit the amount of bot autoattempts from trying to log into your server. Having a password-less ssh port 2942 open is clearly bad, but not when combined with all the standard good practice ssh security.
  • lynndotpy 6y ago
    My understanding is that it's important to keep SSH (and other services) on a privileged port. (I think the default is <1024.) Otherwise, unprivileged malware that could cause the SSH server to crash and take over the (unprivileged) port. No idea if this actually happens in practice though.
• archi42 6y ago
  Yes, I scan them all: 53.2% No, I use default scan: 46.8% 186 votes Well, I doubt that. My private VMs have had ssh listening on some random port for the last decade, after I was annoyed how the auth.log became an inreadable spam-fest. Now it's been well over a year since the last probe. Maybe the author's pentesting pals do that on a few public /24 or some intranet (I would, if I was a pentester). But you're average bad guy scanning /8 blocks looking for an easy catch? Maybe with a botnet... (TBH, I focused on security/crypto during university, but ended up in an other field - so my practical knowledge is limited).
• kazinator 6y ago
  Article misuses/misunderstands the term "security by obscurity", and is attacking a strawman position based on its own definition of what it means. Security by obscurity refers to a situation where security is dependent on the secrecy of an algorithm (the algorithm not being widely known or peer reviewed) rather than (or in addition to) a secret datum used with that algorithm. The opposite practice is to use a well-known algorithm and depend only on the secrecy of the inputs to that algorithm. The layers of security presented in the article do not meet the definition of "security by obscurity". Even a port number like 64235 is a secret datum, not a secret algorithm. It's not a hard-to-discover secret datum; it is poorly guarded. But that's not what "security through obscurity" means. Using a funny port number is a widely-known system, with an objective benefit: it requires an attacker to take certain steps that are not required with a known port number. The assumption is that the attacker knows that alternative port numbers are being used.
• dathinab 6y ago
  Also if the security get much more complex it's not worth it. If it's sheap (initial dev + maintenance + usability) then why not do it?
• ccktlmazeltov 6y ago
  The problem of "security by obscurity" is that it assumes that the whole security is obtained via obscurity, whereas "more security obtained by obscurity" is good as it assumes that obscurity is used as defense-in-depth.
• meowface 6y ago
  Just a tip, since I notice the author included it in their poll: "nmap -p0-65535" can be (almost) abbreviated to "nmap -p-". That excludes port 0 but is otherwise identical.
• perlgeek 6y ago
  Security is not just about preventing attacks, but also about detection and response. In detection, honeypots are very useful, like a machine named gitlab.yourcompany.com in your internal network, but which just alerts SOC about login attempts. That's pretty much obscurity.
• Majromax 6y ago
  > In this post, I will raise my objection against the idea of “Security by obscurity is bad”. I think this article's fundamental flaw is that it conflates the concepts of obscurity and a secret. To start with, a definition: a system is secure if an attacker has no reasonable chance of unauthorized access over a relevant period unless they are in possession of necessary secrets. SSH with public-key authentication is secure by this definition, since the (remote) attacker has no realistic chance of guessing the proper secret key within a human lifetime and there is no better-than-chance way to obtain the secret key. Likewise, a strong, high-entropy password is impractical to guess. Running on nonstandard ports, however? It doesn't add practical security because guessing is so trivial. The author's twitter reach had a 50/50 split on whether they scanned all ports for pen-testing, so that implies that using a nonstandard port increases the time-to-compromise from either (lifetime of the universe) or (about an hour) to twice that, depending on whether the second (real) layer of security is vulnerable. In neither case does the obscure port provide meaningful protection. Some activities like port-knocking can add security, but only if the practitioner thinks of the knocking as a secret from the start. That requires: * Limiting who has knowledge of the secret (i.e.: a port knocking routine known only to you is secret; one distributed in a public client for access to a production service is not), * Having plans in place to change the secret if it is ever compromised (DeCSS) or found to be flawed, and * Ideally ensuring that the secret cannot be guessed / confirmed independently of other secrets. Other suggestions in the article ignore this difference: * Database encryption requires an attacker to possess two secrets for extraction (internal access to the database plus the key) rather than just one. It's not obscurity. * Randomizing variable names or obfuscating code is not a secret because an interested attacker can reverse the obfuscation with ordinary human levels of effort. The confidence here is strictly false, since it "secures" against low-effort attackers and not high-effort ones. The "secret" is distributed publicly, so it is no secret at all. * The convoy example is again a secret; the point is that a would-be attacker does not know which car contains the target and has no reasonable ability to guess with better-than-chance success. Obscurity goes from marginally effective (or outright ineffective) to counterproductive when its implementation makes it harder for the designer to reason about their own system. Someone who rolls their totally unique cryptosystem is relying in part on algorithmic obscurity for their security, but in doing so they give up on established (and battle-tested) best practices in favour of their own limited analysis. Ultimately, the "Swiss cheese" model of security is a poor analogy because a big number for a human is a small number for a computer. To take the convoy analogy again, a would-be attacker is only going to get one shot, but a computer can try billions.
• wgjordan 6y ago
  Indeed, overly broad denunciations of 'security by obscurity' come up as a point of confusion often on HN, and this post provides a good, coherent summary of a proper response. A defense mechanism that only partially mitigates an attack vector could be considered 'security through obscurity' if deployed on its own, but that same mechanism could be considered 'defense in depth' if deployed alongside other defense layers as part of a more comprehensive security model.
• cthalupa 6y ago
  This article misses the point and makes a bunch of arguments that fall apart on anything more than the surface level... much like security through obscurity. We'll look at the SSH port example. What does changing the port get you? You no longer get hit by the automated sweeping that hits basically all internet accessible IPs. Cool! So you had root/password or root/apple or whatever, you were going to get owned by the automated scans, good, you're now more secure. But you shouldn't have been using a weak password to begin with, and now there is a very real risk that you think you are more secure than you were previously. He compares this to animals that have natural camouflage, or the President switching cars in his convoy. But there's no guarantee that you will see an owl in a tree, or be able to determine which car the President is in. But you can scan every port on an IP and find sshd listening with fingerprinting. The cost there is basically zero for someone that wants to attack you. If all I had to do was wait a few seconds longer to make sure I saw an owl or know what car the President is in, then they would not be effective either. You cannot compare situations where there are specific limitations and use them as proof positive for a situation where those limitations don't exist. And this is important: His recommendation to run sshd on 64323 is also just actively making you LESS secure. Ports under 1024 are privileged on Linux - you must have superuser privileges or otherwise be granted access to bind to these ports. No such protections exist for 64323. Now, let's say you have a user level compromise on that server - they start a process monitoring to see if sshd ever restarts/crashes/otherwise stops listening on the port it was listening on, and as soon as it does, they start their own malicious sshd replacement. Now all it takes is someone ignoring the host key mismatch to give away their credentials, which the attack can then likely use to penetrate further into your environment. The author doesn't fully understand the add on effects of his suggestion here, and as a result one of his security by obscurity tips makes you less secure to a focused attacker. Meanwhile, if you REALLY wanted to secure SSH you do not make it listen on internet accessible IPs, and only have it available when you VPN in and access it via a jumphost while using key based auth with 2FA on top of it. When you start obfuscating your code, using random variable names, and generally making it harder to read, how much more likely are you to introduce bugs than you would with a clean code base? Are human introduced bugs more likely to be a security risk than variable names being random? Than code being obfuscated? I don't disagree with encrypting the database, but I also don't consider encryption or password/key protecting something security by obscurity. Basically: Obscuring things helps prevent you from low effort attackers that should not be scary to you to begin with. They do nothing to minimal amounts to protect you from dedicated attackers, and potentially introduce new risks that allow easier access from dedicated attackers. The sort of security measures you should be implementing to stop dedicated attackers will already eliminate the risk from the low effort attackers. NONE of the arguments in this article are new, and they have all been argued against quite extensively in the past.
• Aaronstotle 6y ago
  I like the article overall and agree with the author. Only thing that stuck out to me was when he puts out the twitter poll which shows that a majority of people do scan the entire port range, it defeats the purpose of saying that most people stick to default scans.
• shadowgovt 6y ago
  It has its place; the key thing to remember about it is it's not sustainable. Security by, say, mathematically-hard problems stays secure even when the problem's design is understood. Security by obscurity breaks any time the secret gets out. (There is an overlap point where a math problem is too simple to solve and, meanwhile, an obscure secret is "The sixteen digit number the President memorized to launch the nukes" where the security-by-obscurity can even beat out mathematically-secure, but the middle points of those two sets are separate and the reliability heavily tilted in favor of the mathematical cryptography).
• UI_at_80x24 6y ago
  I like to think of this in military terms. "Don't be where the enemy expects to find you." As TFA and several others have pointed out: (1) Don't use this as your only method of defense. The further from your LOCK the better the key needs to be. (2) Use your security in the layers that offer the most benefit. (3) Be proactive in your defense. -Changing your SSH port will stop that largest number of attempts on your service. -A non-default port PLUS port-knocking PLUS key-only PLUS whitelisted IPs PLUS whitelisted login names. Is better then only one of those. -Apply very liberal firewall rules to prevent any unauthorized from IP's that should have access to your service. Country-code level blocklists are a thing. Being obscure is about NOT being where your opponent expects to find you.
• johnisgood 6y ago
  In many cases it is much better to fake (or spoof) information, rather than try to hide it. Browsers come into mind. Instead of trying to hide information about yourself, which would make you unique, just give them false information that is common, and that way you blend in with the rest of the people, everyone is content, and nothing true has been revealed of you.
• ldng 6y ago
  The bad rep is probably due to too many people having used Obscurity as an excuse to hide the fact the actual security was, at best, an after though for their product.
• fortran77 6y ago
  I agree. If I run my SSH and my VPN on non-standard ports, the number of probes I get a day goes from hundreds to one or two. If I change the admin page of a Wordpress corporate site URL to something other than the standard wp-login.php the number of scripts that try to crack it each day goes from a thousand to zero. It's _very_ effective, along with other precautions for locking these things down.
• zczc 6y ago
  Security by obscurity was the perfect way to send the largest diamond across the world: "Due to its immense value, detectives were assigned to a steamboat that was rumoured to be carrying the stone, and a parcel was ceremoniously locked in the captain's safe and guarded on the entire journey. It was a diversionary tactic – the stone on that ship was fake, meant to attract those who would be interested in stealing it. Cullinan was sent to the United Kingdom in a plain box via registered post." - https://en.wikipedia.org/wiki/Cullinan_Diamond https://en.wikipedia.org/wiki/Cullinan_Diamond
  • rudolph9 6y ago
    Technically a strong password is a diversionary tactic where incorrect passwords could be considered diversions. The difference between what is generally regard as "obscurity" and "security" is orders of magnitude in the number of options one must explore in order to break-in.
• sytse 6y ago
  One downside of security by obscurity is that it makes it harder for whitehat people to spot problems in your code. It is like asking everyone $1000 to look at your source code. It is relatively more likely to deter whitehats since their upside is lower.
  • sedatk 6y ago
    That only works for relatively popular projects though.
• anonu 6y ago
  I seem to recall a story about how a remote server would open a port only after a few unsuccessful calls in sequence to a pre-determined set of ports right before. I've always wanted to set up something like this - but it seems like a pain to remember everytime i want to connect..
• bob1029 6y ago
  Do we feel that honeypots might actually be one form of this? I.e. something that isn't deterministically going to prevent an attack like a OTP cryptographic scheme, but that may trick a large majority of attackers into thinking they are actually in a secure production system for a long time. I know they are used primarily for detection, but why not go the extra step and make a honeypot that is a truly believable facsimile of a real corporate environment so the attacker wants to stay around even longer. There are lots of clever ways you can switch network traffic to make it look like you are talking to one host when in reality you are talking to a VM jail under a security administrator's desk. Load these environments up with fake, but believable data. How would an attacker know if they are in production actual, or fake prod? Once you "acquire" an attacker, you could even monitor their approach and string them along with hopes of getting into SVRSQLPROD (which is obviously going to be loaded with fake bullshit, but they wont know until they find the symmetric encryption key which you will probably never give them). Again, I think we are all clear that the above is not deterministic security and that certain experienced attackers (or insiders) may be able to smell such a honeypot from a mile away.
  • waihtis 6y ago
    Preface: May be biased, as I run a honeypot company. To your question: absolutely. They are also a very economically effective and (done right) an easy-to-implement solution with very low-to-none risk of jeopardizing any legitimate traffic. To your why not do this - we are working on this right now. There's a lot of interest to what you described in above average maturity security teams; we have a few customers in this niche helping us design the "attacker playpen." You are right in that it is a challenge to make believeable enough without introducing risk into the environment.
• stjohnswarts 6y ago
  Security by obscurity is dumb to count as part of your main toolbox of tactics. However it can be icing on the cake, like moving ports around and turning off ssh root login at all. Lowering your footprint never hurt. Sometimes you just have to run a little bit faster than the other guy if you're being chased by a bear.
• waihtis 6y ago
  I run a cyber software company with a product basically structured on this principle (deception.) The swiss cheese picture is excellent, since that is how stuff happens in the network internals, with lateral movement and other internal activities. Say an adversary has to jump 5-10 hops from initial point to target system and you can, with very lightweight obfuscation and ”obscurification”, increase the attackers mistake rate dramatically - it makes a ton of sense from a risk and economic perspective. Consider the alternative (succesful internal hardening and monitoring) which is way out of scope resourcewise for most.
• austincheney 6y ago
  risk = probability * severity Security by obscurity is bad regardless of other controls because it does little to reduce probability of attack and nothing for severity. It is only barely helpful at reducing the probability of attack because it is ineffective against various forms of automated footprinting. That is just the attacker. Security controls impact everybody though. Not only does it make the problem obscure to an attacker it also makes the problem obscure to non-attackers. This dramatically increases risks because it impacts the application and distribution of other security controls. Since it’s barely helpful where intended and harmful where it’s unintended security by obscurity only increases risks. The analogy to software is the belief that hiding source code makes it safer. Hidden source code is not any safer but the vulnerabilities are a bit harder to find. The benefit of open source is that the vulnerabilities are exposed to anybody who reads the code which allows more vulnerabilities to be exposed and patched.
  • arduinomancer 6y ago
    Ehh the majority of companies practice security by obscurity as an extra layer. There's the idea in security that an attacker knowing your algorithm/practices shouldn't mean anything yet you rarely see companies detail the security measures they take on internal systems because we know keeping this secret has no downside.
    • austincheney 6y ago
      Popularity does not validate stupidity. Security policies at most companies are often generic and not secret. Reporting chains for emergency remediation and asset identification are secret because those identities are potential attack vectors. Information sensitivity of that nature means it must be protected from disclosure and not that it should otherwise be hidden. The key phrase for sensitivity management is: need to know.
• riquito 6y ago
  It's like a painting in front of a safe: - doesn't reduce the security of the safe - ensure you don't advertise "THERE'S A SAFE HERE" to whoever visit your house, possibly reducing burglar attempts Now, if you have just the painting over a hole in the wall, you got something wrong...
  • cthalupa 6y ago
    Now, assume that every painting in your house can be checked for a safe behind it in milliseconds (total, for all safes) by the people in your house. Did you actually accomplish anything?
    • choward 6y ago
      Yes, let's say you have random people over you don't know (to fix things for example). One of them is a criminal that wants to case your house to see if it's worth bteaking into when you're out of town. If you're with them the whole time they are working, they won't be able to just look behind the painting and your house doesn't become a target. That's assuming of course that the painting isn't too valuable.
      • cthalupa 6y ago
        But that scenario now takes us firmly outside the realms of what we’re discussing here. You’re actively monitoring the actions of people that you know are going to be there. For an Internet facing server, it would be more like an art gallery where you have hidden the safe behind one painting, and the gallery is open 24/7 with no security to stop people from looking behind paintings, where you know a good portion of visitors are going to do so. You can see an identifier for each visitor that looks behind paintings, but many visitors are doing so and the person that comes in to crack the safe might not have been the person who found it.
    • riquito 6y ago
      Why would you think it's in milliseconds? Are you generalising on port scanning? You could say that uuid as urls are obscurity, but it's not that fast to break through (and then hopefully you get some kind of protection layer) There's also an additional monetary cost for the attacker, it adds up
• MrXOR 6y ago
  Security by obscurity is dangerous. You can eliminate any obscurity with reverse engineering, spying, etc. Obscurity makes your system prone to catastrophic collapse and loss of security. Security by open design is necessary but even insufficient.
• lizknope 6y ago
  I bought a new virtual machine and I waited about a day until I logged in. The SSH logs showed over 100 failed login attempts. I hadn't even logged in! I changed the default SSH port to a random high number. I had zero failed login attempts in 2 months. Of course use strong security methods but I suggest changing the default port numbers just to clean up the log files.
  • rudolph9 6y ago
    What ports did the firewall have open?
• yalogin 6y ago
  The author doesn’t understand the phrase “security by obscurity” and doesn’t know why we use that. He took the normally used phrase literally and ran with it. The phrase is used to suggest developers shouldn’t think that obscuring something provides security. We don’t say not to obscure stuff. In fact all the examples in the articles are from what’s already used in products. So the security community uses the best available method to secure the given task/stack already.
• choeger 6y ago
  I think the article confuses two concepts. "Security by obscurity is bad" usually applies to things like "our own proprietary hash function", or "our own proprietary remote control protocol", or sometimes even just "well, noone has the code, right?". I call this obscurity proper. This is often little more than an omission. All the positive examples in the article mean actively obscuring the view of an attacker. This is an addition of things like camouflage or distraction. Proper obscurity is obviously bad, because there simply is no security concept behind it. Additive obscurity is obviously smart because it adds to an existing concept.
• Jumziey 6y ago
  This article is so odd in its conclusion. The problem lies in obscurity generating a mess thats hard to reason around by designers, hiding obvious weakpoints, making it hard to find the most valuable area to work on. Changing from a default port should not really count as this since its easily configurable and does not impact neither the design nor usability (unless it does). Port scanning avoidance also fills an actual function in terms of load issues. Rather what seem to be the issue is what security by obscurity actually means and can be missinterpreted as. Layering lots of obscurity and putting time on that when it can be spent to increase security in the actual weakpoints or/and hiding them for developers/maintainers are problematic to say the least.
• greyhair 6y ago
  Obscurity takes many forms, and some are useful, particularly to common hackers, and others are completely useless. There are a number of code walking tools and disassemblers that will rename all variables and function linkages and provide annotated source. Someone still has to crawl through that source, but all the obfuscation is removed. I know professionals that use these tools, not to hack, but to perform security audits on products that they use within highly secure settings. I attended a security conference a few years ago, cannot think of the speakers name right now, but he said you should assume that professional hackers have better tools and larger budgets than you will ever have access to.
• kseifried 6y ago
  Making security by obscurity actually work The reality is security by obscurity CAN work, but only if three critical elements are met: The first is to know when the obscurity has failed The second is to be able to quickly change the obscured component (e.g. a password) The third element is the hardest, security by obscurity only really works if you can survive exposure of the obscured data/system Which leads to the fourth element: security through obscurity IS NOT security through secrecy (so either I'm a liar or bad at counting, leave your vote in the comments below) Let's start with the 4th element, obscurity vs secrecy. Passwords. Passwords generally only work if they are secret. Some password systems like Kerberos take great pains to ensure passwords remain secret, for example by NOT sending the password itself to a remote system, but by sending proof that the user has the password (grossly simplified, but generally correct, now you understand Kerberos!). Secrecy involves hiding things that if exposed will be a problem that can't be solved, like your password, the formula to Coca-Cola and so on. Obscurity won't work for things that need to be secret. Obscurity won't work for things that once exposed result in the game ending. Even when an item can be obscured, it is still important to know when it is no longer obscured, otherwise you now have an element of your security system that has effectively been breached. For example if you are using randomized port numbers to prevent SSH scanners from constantly trying default username/password combinations and someone (like shodan.io) port scans you and publishes your SSH server ports you either need to change that, or not be relying on that obscurity for your security (e.g. I used to change my SSH port #'s just to reduce logging activity and make it easier to filter/read logs for actually malicious activity). The second element is that once your obscurity becomes known you need to be able to change it, if you can't change your SSH port # (because you don't have a way to tell clients where it is) then you have a security control that cannot be recovered and you lose it. Security elements should always strive for long term survivability because the simple fact is attackers get to try more than once. The third and final element (because we started counting at 4!) is your system cannot simply fail because the obscure element was discovered. Using a no standard port for SSH works if you also use strong passwords or (ideally) key based login. Obscuring SSH ports and leaving a default admin:1234 login is brittle, and as evidenced by scanners like shodan.io easily exploited. I think, honestly, the best use case for "security by obscurity" is to cut down on the noise of logs and casual scanning/scripted hacking, which can be valuable, having less chaff to sort through for actual attacks can both save time and money, but also give you a better chance of finding the real attacks. https://app.voice.com/post/@kurtseifried/making-security-by-obscurity-actually-work-1599853811-1 https://app.voice.com/post/@kurtseifried/making-security-by-...
• Havoc 6y ago
  The people arguing against "security through obscurity" seem to have an implicit assumption that you're not also doing proper security. e.g. I move my SSH ports to a high port. But I also ed25519 keys. I think the port helps though. Plus keeps the logs clean.
• server_bot 6y ago
  Fun article! I'd add that malware packers are a good example of an obscurity layer that's typically effective in practice. But food for thought: in the general case you can't reliability predict the efficacy of an obscurity mechanism, so you never know if it's an actual layer of defense or a placebo.
• snowwrestler 6y ago
  All software security comes down to obscurity: it depends on the selection of specific numbers that are known to the authorized parties, but are extremely difficult to guess (i.e. very obscure) to the unauthorized parties. The extreme of this strategy is to make a successful guess cost more than anyone can possibly pay, for example by using numbers so obscure that all known algorithms for guessing them will take longer than the heat death of the universe to succeed, or something like that. But while there seems to be solid math to calculate such numbers, implementations are rarely perfect and can easily leave open the possibility of other guesses that cost a lot less than breaking the theoretical limit. (AKA side channels, vulnerabilities, bugs, etc) Where "security by obscurity" comes in for criticism, it's usually because the implementers have misjudged the amount of obscurity they are actually creating, or misjudged the amount they need (their threat model), or both. It's easy to make these mistakes because it is hard to create perfect implementations, and hard to know exactly the current and future capabilities of your attackers.
  • iso8859-1 6y ago
    Security can also be achieved by physical separation or identity based on physical human traits. Now we're getting philosophical, but if the security crew of the data center knows my face, and does not allow other people to enter, would you reduce my face to a value that is "extremely difficult to guess"?
    • bosswipe 6y ago
      Right. There are three types of authentication factors: something you know, something you have, something you are. Obscurity and passwords fall under "something you know". Biometrics like what you describe would fall under "something you are". A physical key such as a yubikey or the sim card matching an SMS challenge would be "something you have". Multi-factor authentication is more secure but it doesn't negate the discussion here about hardening the "something you know" factor.
      • chrononaut 6y ago
        What's interesting is that (mostly impractical at the moment) attacks on biometrics authentication mechanisms end up summarizing that category to also "something you have", rather than "something you are" -- not that it negate its particular utility.
• aazaa 6y ago
  This article could benefit from a definition of "security by obscurity." Every crypto system is based on obscurity of one kind or another. That private key, password, or token is just an obscure form of information that may yield, eventually, to a brute force attack. Or not. It's really hard to know for sure.
  • iso8859-1 6y ago
    Does this mean that https://en.wikipedia.org/wiki/Provable_security https://en.wikipedia.org/wiki/Provable_security does not exist?
• ocdtrekkie 6y ago
  I can't tell you how many times I've seen someone say doing something for obscurity shouldn't even be done because of the adage. Some of these adages are really harmful. InfoSec has very much gotten a bunch of these statements that can't be argued with, and people won't even take you seriously if you point out the flaws with password managers or PKI. I've definitely used methods in my own code which "aren't trustworthy" from a security doctrine standpoint, but proven near 100% effective, on their own. Just because a state actor won't be phased by it doesn't mean it isn't a strategy that'll prevent 99% of automated attacks.
• LordOfLamers 6y ago
  Be different from other one else, stay calm forever.
• kjgkjhfkjf 6y ago
  Yes, making security breaches harder for attackers at zero cost is obviously good. But obscurity does not have zero cost if it makes the system less efficient to operate. Having multiple cars in a presidential convoy is inefficient; using non-standard ports adds complexity; obfuscating data makes debugging harder; etc.
• adontz 6y ago
  I think the article misses more important attack vector focusing on brute force, instead of human weaknesses. Obscurity is naturally fragile, vulnerable to social engineering. Social engineering is the real problem. We can filter out brute force easily. It can be fail2ban, or even simplest ip-tables rules like iptables -A INPUT -j REJECT -p tcp --dport 22 -m state --state NEW -m recent --name TCP_SSH --update --rttl --seconds 600 --hitcount 15 --reject-with icmp-port-unreachable iptables -A INPUT -j REJECT -p tcp --dport 22 -m state --state NEW -m recent --name TCP_SSH --update --rttl --seconds 60 --hitcount 5 --reject-with icmp-port-unreachable iptables -A INPUT -j ACCEPT -p tcp --dport 22 -m state --state NEW,ESTABLISHED -m recent --name TCP_SSH --set If you move from passwords to SSH keys, it increases security not really because number of possible keys is larger than number of possible passwords. More important is that you eliminate bad practice. One cannot share SSH key over phone conversation, write it down on a piece of paper and stick it to a monitor. Change is nothing similar to upgrading from 1024 bit SSH keys to 3072 bit SSH keys. If you store SSH key on some HSM, like YubiKey, even better, no one can copy this key, only steal. You cannot really hide IP address or port number. You'll send this information to your colleagues and partners over SMS, Facebook Messenger, Whatsapp, Viber, Telegram, E-mail, Skype, Zoom, many times, multiple channels. Or you will write it down on a Wiki, like Confluence, which is public to entire organization, and that knowledge is not a secret anymore. My greatest fear is not a script kiddo with botnet, but an addict employee with debts.
• CodeArtisan 6y ago
  A field where obfuscation is very common is commercial video games where they are now up to the point of using a virtual machine that generates an instruction set randomly at compile time to obfuscate some part of the code. These games are still cracked almost on release day. https://en.wikipedia.org/wiki/Denuvo https://en.wikipedia.org/wiki/Denuvo
  • somerando7 6y ago
    It makes the barrier to entry MUCH, MUCH higher. First you have to unpack a binary, THEN you have to fixup any custom VM call that it makes. Basically only incredibly specialized people/groups will be able to do this. Contrasting to games of the 2000s the barrier has been raised significantly for hackers
  • ChrisLomont 6y ago
    Most PC game sales occur in the first 30 days after release. Protecting even a few days adds significant value to the publisher. Some protection methods do last a long time. StarForce 3.0 protected SplinterCell took 422 days to crack. Not long ago cracking Denuevo protected games took around 75 days [1,2]. I'm not aware what the current best protections are or how long such protected games take to crack. [1] https://news.ycombinator.com/item?id=21953764 https://news.ycombinator.com/item?id=21953764 [2] http://web.archive.org/web/20200104093734/https://iscracked.info/statistics_denuvo http://web.archive.org/web/20200104093734/https://iscracked....
• catears 6y ago
  While the article does have a point that obscurity can improve defences, I think security is not about defence. Security is about managing risk in a consistent and rational manner. This means that any defense mechanism need an appropriate level of defense against the threat. Having a network share on the home network that only your household can access and use 2FA for that? Maybe a bit too much. Do you know your organization will be individually targeted by smart and tenacious actors? Changing the SSH port isn't gonna stop them. I agree with the article that more discussion about what makes something secure is valuable security work. Disregarding defenses at first sight because they "sound obscure" isn't a good argument. But it also doesn't mean that "small things that might stop someone" is a good layer of defense. And then there is also the cost of adding security layers...
• calibas 6y ago
  I think there's two different things we're talking about here, one is hiding things and the other is using obscure ways of doing things. Changing your SSH port is the former. Using NETRJS instead of SSH is the later. Hiding things is just a good security practice in general (just understand hackers have access to port scanners) so that kind of "security through obscurity" isn't a bad idea. Using obscure protocols is something quite different, and really shouldn't be in the same category.
• random3 6y ago
  Security by obscurity naturally transform security into a probability. When you use given hard opaque rules (e.g. TLS + X Y Z) you stop thinking in depth. Instead when you think about layers of obscurity, you go much deeper affecting the probability at each layer (host, port, etc.) In reality, at a different conceptual level, things like TLS are also bundles of obscurities.
• resfirestar 6y ago
  In my opinion the SSH example with a non default port, random username and easy password is a perfect example of a bad kind of security through obscurity: instead of a user friendly and foolproof approach (disabling password authentication and using keys), we introduce multiple layers of obscurity that make life harder for the sysadmin and users, which collapse as soon as someone creates an account on the box without a sufficiently obscure name. When it inevitably fails (either because of the aforementioned reason or because a global scanner has the clever idea of trying some more obscure usernames) everyone looking back on it will wonder why you built this Rube Goldberg machine instead of just using SSH keys. Changing the RDP port is a slightly better example of actually using security through obscurity as a defensive layer because Microsoft doesn’t give you any good ways to lock down RDP (best practice is of course keeping it behind a VPN or using a Remote Desktop solution with a more modern authentication system), but from a practical point of view I know several companies that were hit with ransomware this year via RDP on a non-standard port. I think they would rate the risk reduction from that approach pretty low. Finally, symmetric database encryption is not an obscurity measure, as the author himself points out it specifically protects data against an attacker who can query the database but not find the key. Whether the attacker can get the key is a matter of capability not determination or luck.
• noncoml 6y ago
  In Applied Cryptography, Schneier says obscurity is "take a letter, lock it in a safe, hide the safe somewhere in New York". Somehow in my mind, cryptography, eg. RSA, is also obscurity then. But instead of obscuring the physical coordinates in the set of coordinates of New York, we obscure the location of the private key in the set of prime numbers.
  • jariel 6y ago
    Lock it in the safe, hide it ... but then forget about the safe and make sure everyone else has as well. Then it doesn't exist.
• nitwit005 6y ago
  These days you have to assume hackers have read the engineering new hire guide that you wrote up. The SSH port will probably be in there. A big tech company will have tens of thousands of current and former employees. Those employees may try to break in, and all the easily accessible internal wikis or other common resources are going to end up on some hacking forum somewhere eventually.
• beams 6y ago
  Sure, it adds a little bit of “security” like the camouflage on tank example, or the prey jumping. Those examples are poor however, because — unlike changing default ports, adding knocking, obfuscating code - these examples are extremely low maintenance/cheap, and come with essentially no downside. What’s missing here is the discussion of tradeoffs. I fail to see how e.g., requiring port knocking adds enough security to justify the annoyance. Changing the default port, maybe, but given how easily it’s detected anyway, the cons still outweigh the pros IMO.
• hnruss 6y ago
  The problem with security through obscurity is the false sense of security that it provides. This in itself can lead to vulnerabilities. Regarding data obfuscation, for example: - Can an average person differentiate between encrypted data and well-obfuscated data just by looking at it? - Would it be reasonable for the average person to assume that obfuscated data is equally as "secure" as encrypted data? - Might someone store and transmit "secure" data differently than normal data?
• maitredusoi 6y ago
  My 2 cents : use port 26, it is below 1024 and assigned to various other things... so you are hidding better !
• User23 6y ago
  I practice security through obscurity every day. For example I don't flash large amounts of money when out in public. The notion that security through obscurity isn't security is and always has been monumentally stupid. In some sense sure cover is better than concealment, but in the real world 100% concealment is better than 100% cover since in the former case one won't be taking fire at all.
  • kag0 6y ago
    the problem with that (and security through obscurity in general) is that if your opponent attacks at random, they still have a chance of getting you. having lived in a bad neighborhood I can tell you that you don't have to flash money, or even look like you have any money to get into trouble (someone chooses you at random for a gang imitation, crackhead wants your shoes, or someone is just straight up crazy). it's always better to have as much cover is reasonable, and beyond that concealment doesn't hurt.
• wglb 6y ago
  Raising the cost of attacks is a good thing, particularly if the cost of doing so is not too great. However, beware that obscurity is in the eye of the beholder, or more relevantly, in the eye of the attacker. For example, script kiddie attackers may be the ones who in the twitter example only scan the default ports. This is an important element to defend against. But a seriously skilled attacker isn't going to use script kiddie methods. They will use more complete, likely stealthy attack patterns. Bear in mind that what you think of obscure may be breakfast for a skilled attacker. If you are serious about defense, then you will be compelled to follow the ninja threat model, which, in part, says The attacker is going to sit on the same network segment as the application. There’s no firewall or filters. There’s a special place in hell reserved for products that require firewalls or filtering to protect themselves against attack. Focus too much on obscurity and you will fall victim to the fallacy of "defense by presumed motive."
  • BlueTemplar 6y ago
    Is this why ~half of the people say that firewalls are not worth it for IPv6 ?
• valgeirg 6y ago
  I am not going to read the article because i am to lazy, but I agree.
• worker767424 6y ago
  Aren't passwords just security through obscurity?
• throw149102 6y ago
  One point I haven't seen brought up yet is that anywhere from 25% to 35% of data breaches are related to an internal actor. Your obscurity will do nothing in those cases, because the internal actor will actually know about the obscurity. That being said there is a place for obscurity in security, it just has to be traded off with the usability issues.
  • sedatk 6y ago
    He didn’t claim it works for all cases. But it works for some cases, such as throwaway accounts.
• deleted 6y ago
  [deleted]
• blackflame7000 6y ago
  Another name for security through obscurity is stealth
• shuringai 6y ago
  "if you can reduce risk probabiloty with zero cost..." since when is obscurity zero cost? You've seen how much denuvo and vmprotect cost? Can you name any free free code obfuscator besides proguard that actually works? Can you name one that supports golang or rust? Security trough obscurity is considered bad because it's not zero-cost, and the investment you put into it might rather go into actual security
  • sedatk 6y ago
    Changing the port number is quite cheap.
    • austincheney 6y ago
      That is also not a security control.
      • sedatk 6y ago
        Theoretically, yes. But if it makes you get off the radar of some malicious attacker who is capable of exploiting you, then the mission is accomplished.
        • austincheney 6y ago
          Not at all. The attacker will find it within a minute after running a port scan.
          • sedatk 6y ago
            Not applicable to mass scanners. They simply can’t afford scanning all ports for all hosts.
• zaptidizap 6y ago
  I like passing around a bunch of completely meaningless "keys" and passwords that innitially always fail.
• _emacsomancer_ 6y ago
  If the security-by-obscurity means binaries that you don't have the sourcecode to running on your systems, not only is that such a 'security method' not underrated, it's downright dangerous.
• mindfulhack 6y ago
  The ironic thing is that it would be logical not to share or publish examples of security by obscurity, in order for them to be more effective! Doesn't that reveal part of the problem of 'security by obscurity'? Indeed, how many people publicly disavowing 'security by obscurity' do so to secretly benefit from the methodology?
• m3kw9 6y ago
  Ppl that say obscurity is bad must be saying look here try hacking my site, it’s unhackable and secure. Everyone knows it’s good, it just make you look weak to say obscurity is useful. Ppl are scared to admit how useful it is in security.
• kempbellt 6y ago
  The best security is telling people: I have a super secret password to my bank account! It's super hard to guess, and there's 12 factor authentication. You have to get my cat's paw print to sign in. When the truth is: There is no bank account, password, or cat. And you are actually a homeless, broke, dog lover. If you want to keep something secure, don't brag about how secure it is. Don't talk about it at all.
• throwaway45829 6y ago
  Utku, try to enroll in a PhD program. You are wasting your time with this BS nonsense.
• ac42 6y ago
  Passwords / keys are obscure by definition. With this in mind, "Security by Obscurity" technically adds one or two bits to your key.
• peterwwillis 6y ago
  Risk is not just a formula. Risk is also "formulaic": when you get people used to an idea, they become blind to things outside of that idea, and there in lies the danger. If your corporate IT group regularly asks users to send in their passwords via e-mail in order to perform some remote maintenance, then the users will be habituated to sending their password to a familiar e-mail address. If someone from outside their company asked them for their password, they would immediately say no. But an e-mail with the right "From: " address, they would quickly fall for. So it becomes easy to trick the users into sending their password to an attacker in some circumstances, because of the assumptions they make. Security by obscurity is just another form of this: a practice which isn't really secure, but people may think is secure, because it seems to avoid the simplest, most stupid attacks. But literally any action you take could prevent the simplest, most stupid attacks. That doesn't mean that any action you take makes you "more secure". Hiding a key under a door mat or in a sun visor isn't "more secure" than leaving it in plain view. Anyone who's not a total moron will find it, and if that's your whole security posture, you're screwed.
• paradox242 6y ago
  Yes, this is one of those rules that is designed for novices. It's actually a reasonable part of any security strategy for the reasons you mentioned.
• RedComet 6y ago
  This has always been obviously true. The only sense in which the (original) phrase has any meaning is with respect to cryptographic primitives. And even then, all a cipher is really doing is "obscuring" data. I've never really heard anyone other than Steven Gibson subscribe to the silly phrase.
• BorisMelnik 6y ago
  yes agree with this whole heartedly - have been using security by obscurity in my servers, home and office for 30+ years probably since I learned about it in the Linux Bible or something like that. I don't think anyone assumes when people say "security by obscurity" they mean "only" it is a great layer to add in addition to. In my home for instance, the entire back of my house is hidden with 10 foot trees so when people drive by the road, they don't see my house. Now I've got a deadbolt, alarm, cameras, a dog, and a gun to add to my layers but having those trees there is a nice feature.
• deleted 6y ago
  [deleted]
• axaxs 6y ago
  I don't buy the poll, at all. When I move SSH off port 22, I don't get 50 percent traffic. I get 0 percent. It's the first thing I do to harden any server.
• arendtio 6y ago
  In my opinion, the article misses the point: Security by obscurity might be beneficial, but it is by no means as strong as real security. So the problem is, that people who take the obscurity road, might not care so much about the rest. Security by obscurity is simply a completely different class, comparable with dollars and cents. So if you care about security would you rather focus on the dollars or on the cents?
• rgj 6y ago
  It was never “security by obscurity is bad” It was “do not rely on security by obscurity”
• blackflame7000 6y ago
  Security through obscurity is not fool proof, but neither is cryptography in general. It's all about making the problem as difficult as reasonably possible. Someone could guess a private key by incredible luck according to Murphy's law and while the probability of that happening is so extremely improbable, it is not zero, and therefore not foolproof.
• nightsd01 6y ago
  Rolling your own crypto: most definitely a bad idea. Using existing best security practices AND adding in a few low risk plot twists: genius.
• catears 6y ago
  I want to tackle a misunderstanding I have seen from some posters in this thread about passwords/secrets/keys. Using a password should not be considered a form of "obscure defense". If you are using a password there is a mathematical definition of how hard it is to crack, the number of bits of entropy contained in the password. If you use a password manager like KeePass it will tell you the number of bits in you password. If it takes me 2^100 guesses for a 50% chance to discover your password then that is not obscurity, that is a valid defense mechanism. That the password itself is obscure is not a reason to call the strategy obscure. Passwords and keys are used to create an artifact that will unlock access to a whole bunch of information. Instead of protecting each piece of information individually, we can now focus our efforts on protecting the password instead. With a password we have managed to make the process of protecting information simpler, less obscure. Sorry to discuss something a bit off-topic from the article, but I figured I had seen the "passwords are obscure" argument so many times here and that this could be a valuable opportunity to teach something about security.
• helsinkiandrew 6y ago
  Unless you are Goldman Sachs, the NSA or someone else who is being specifically targeted this is always true. Otherwise, switching ports or making your systems a bit different to the others on the internet means the majority of hackers - 'bots', 'scanners' and 'script kiddies' will move on to easier targets. On the internet you don't have to outrun the bear, you just need to run faster than some other guy.
• KingOfCoders 6y ago
  I agree, I change the SSH port on all machines and have much less hacking results from drive by hackings. Security-by-obscurity doesn't replace real security of course, but it removes a lot of noise.
• petjuh 6y ago
  I've often wondered about using an older OS such as OpenVMS for which hacking tools simply don't exist.
  • wglb 6y ago
    Good hackers make their own tools over a weekend. And if it is open . . . See https://nostarch.com/bughunter https://nostarch.com/bughunter
• simonjgreen 6y ago
  I am a strong believer in the Swiss cheese model[1] of risk mitigation. I first learnt about this through pilot training and apply it throughout my professional life now. A lot of comments here are saying "don't do x, do y." or "x and y are useless, you should just do z". The Swiss cheese model helps you visualise that adding and recognising having many layers of defense carry value and should be recognised as such. 1. https://en.m.wikipedia.org/wiki/Swiss_cheese_model https://en.m.wikipedia.org/wiki/Swiss_cheese_model
• phs318u 6y ago
  One problem with “obscurity” is that - by design - as few people are aware of the detail as possible (otherwise it’s not obscure. That’s both it’s strength and it’s weakness. With far fewer eyeballs on it, it’s easy to think you’ve gotten it right, when in all likelihood you’ve probably gotten it wrong (somewhere).
• aschatten 6y ago
  Didn't Telegram challenge this rule as well? > * Never roll your own crypto Afaik, discovered practical vulnerabilities like [1], [2] were patched, and the rest are theoretical, like [3]. > Using Symmetric Encryption in the Database: When you write data to the database, use a function like encryption_algorithm(data,key). Likewise, when you read data, use a function like decryption_algorithm(data,key). If the attacker can read your backend code, obviously he/she can decrypt your database. I think the author misclassified this method. An actual encryption is not obscurity. It would be, sort of, if the key is stored in code. But when a proper key management is in place, it's a solid approach. [1] https://news.ycombinator.com/item?id=6948742 https://news.ycombinator.com/item?id=6948742 [2] https://web.archive.org/web/20181118154823/https://www.alexrad.me/discourse/a-264-attack-on-telegram-and-why-a-super-villain-doesnt-need-it-to-read-your-telegram-chats.html https://web.archive.org/web/20181118154823/https://www.alexr... [3] https://eprint.iacr.org/2015/1177.pdf https://eprint.iacr.org/2015/1177.pdf
• nickcw 6y ago
  I'd argue that all security is security by obscurity, it is just a question of how many attacker-seconds it takes to break. Obscurity means keeping something private that if the attacker knew they could access your service. Traditionally security by obscurity is something like putting your ssh login port on port 61329 rather than port 22. I'd argue that the above is 16 bits of obscurity, whereas your ssh key you log in with is 1024 bits of obscurity. The attacker needs that 16 bits of port number obscurity and the 1024 bits of ssh key obscurity to log in. However the attacker-seconds to break the 16 bit port number is a rounding error compared to the attacker-seconds to break the 1024 bit ssh key Which is where, I guess, the idea that "security through obscurity" is bad came from. I'd argue that the attacker-seconds is still higher with your ssh on port 61329 though, so why not use that too.
  • athrowaway3z 6y ago
    Ik like this taken on it. But the math isnt complete. You need to account for each attack path taken. For example: a generic SSH vulnerability means somebody is going to make a botnet to check every port 22, leaving your 1024 bits useless and the 16 bits worth more.
• zemnmez 6y ago
  Security by obscurity is harder to reason about. Heavily obfuscated code is always more insecure once the obfuscation is reversed. The other big difference is you can incrementally break it; you are not going to be privy to if someone is selling your deobfuscated code online. Lastly, the example of randomising the presidential car i’d likely not call security by obscurity. Security by obscurity does not mean that there are secrets inherent to the protocol (or private keys would be obscurity!) if it was the same car every time, and they relied on nobody telling anybody, that’d be security by obscurity for me, otherwise it’s just a random value with a low keyspace
• deleted 6y ago
  [deleted]
• lowwave 6y ago
  Totally! Security by obscurity is awsome!!!! Had a software running for over 10 years for many users. Never a hack because the backend is some very obscure framework on jvm. Just upgrade the JDK and everything still runs fine after over 10 years.
  • lowwave 6y ago
    However, comments like "SSH runs in port 22 and my credentials are utku:123456. What is the likelihood of being compromised?" You have any idea what kind of RAM and computing power an average user have access now days. Think of better obscurity abstractions than that. Try bcrypt/scrypt hash your shadow password on linux.
• Merrill 6y ago
  "Roll your own crypto" may not be entirely bad either. Suppose that you encrypt your message using "my own crypto". The result is ciphertext that looks like a random bit sring. Then encrypt the ciphertext using a standard algorithm such as AES. An attacker will have difficulty since a successful decryption of AES is hard to recognize as such.
  • thomasahle 6y ago
    Or you could spend that extra compute on just using a longer AES key. (Or if you distrust AES itself, make your second layer some other well thought through encryption scheme.)
• electricant 6y ago
  Just as a side note, moving your ssh server port from 22 to whatever may make your server unreachable under strict firewalls. If you are allowed to connect to some whitelisted ports then it's highly unlikely that port 64323 will be allowed.