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(1) a one time pad is and will remain highly secure (2) blocking shortwave radio (even if you are a nation state) is more difficult then taking down web assets.

(1) a one time pad is and will remain highly secure (2) blocking shortwave radio (even if you are a nation state) is more difficult then taking down web assets. (3) there are benefits to security by obscurity when its part of a layered approach with constant maintenance and feedback (#3 is my controversial take)

cqqxo4zV46cp 2y ago
The fact that 3 is controversial is telling of the sad state of the security knowledge of techies generally. The most people seem to be able to do is to cargo cult / parrot, misunderstand, and misappropriate quips like “security by obscurity bad!” when it, all else equal, is a perfectly reasonable and often useful additive measure to take if it’s available to you.
- willis936 2y ago
  You can even poke holes in it using their own terminology. Obscurity is equivalent to minimizing attack surface area. The less adversaries know about your system the smaller of a target it is.
  - noduerme 2y ago
    I think there's overlap between surface area and obscurity, but they're not equivalent. To use the most pedestrian example, moving SSH off of port 22 makes it more obscure, but the total surface area hasn't gotten smaller.
    - thyrsus 2y ago
      Anecdata: log files with failed login attempts became far smaller after leaving port 22.
- kibwen 2y ago
  A knee-jerk aversion to anything halfway adjacent to "security by obscurity" is flawed, but this reaction to that aversion is also flawed. Instead of trying to suggest "security by obscurity is fine, actually, and don't worry about it", it's time for us to just stop being pithy and start being precise: your cryptosystem should be secure even if your adversaries understand everything about it. If that is true, then you can (and, in the real world, almost certainly should) add defense in depth by adding layers of obscurity, but not before.
- chmod775 2y ago
  > The most people seem to be able to do is to cargo cult / parrot, misunderstand, and misappropriate quips like “security by obscurity bad!" That is the point. It is a good rule of thumb for people who don't know much about security. Anything they create trying to add more security to their system is more likely to do the opposite. If you think you know better, feel free to ignore it. Just be aware you wouldn't be the first who thought they knew what they were doing or even the first who did know, yet still messed up.
- ef32d2d 2y ago
  Yeah. I think it's the result of conflating theoretical cryptography and practical IT security. Kerckhoffs's principle is true in the theoretical domain and it's certainly important that the designers of standardised crypto algorithms adhere to it but it doesn't follow that it's pointless to change your SSH port.
- adrian_b 2y ago
  While “security by obscurity” may be good for some spy agency as an additional layer over a system that would remain secure even if it were published, most people are right to say that “security by obscurity bad!”, based on the known history of such systems. The reason is that, without any exception, every time when some system that used “security by obscurity” has been reverse engineered, regardless if it was used for police communications, mobile phone communications, supposedly secure CPUs etc. it was discovered that those systems have been designed by incompetent amateurs or perhaps by competent but malevolent professionals, so that those systems could be easily broken by those who knew how they worked. “Security by obscurity” is fine for secret organizations, but for any commercial devices that incorporate functions that must be secure it is stupid for a buyer to accept any kind of “security by obscurity”, because that is pretty much guaranteed to be a scam, regardless how big and important the seller company is. Obscurity is OK only when it is added by the owner of the devices, over a system that is well known and which has been analyzed publicly.
- Natsu 2y ago
  This misunderstands how "security by obscurity" came about, because there are good and bad types of obscurity. Back in the 1800s people were selling shoddy locks that were easy to pick and they were mad that people were disclosing lock picking methods: https://www.okta.com/identity-101/security-through-obscurity/ https://www.okta.com/identity-101/security-through-obscurity... This history repeated later, with people making shoddy cryptography where they didn't want anyone to know how it worked, and similar things, most of which got broken in embarrassing ways. This sort of obscurity was actively harmful and let people sell defective products that people relied upon to their detriment. Meanwhile, there are good types of obscurity, too. For example, there are the information disclosure CWEs that tell users of products not to disclose version numbers, stack traces, etc. to users, and this sort of "obscurity" is perfectly reasonable and widely accepted. So it's not the case that all things that might be termed "obscurity" are bad.
localfirst 2y ago
" there are benefits to security by obscurity when its part of a layered approach with constant maintenance and feedback" im not sure i understand what this means, can you provide an example and why its controversial? do you mean a one time pad using memes via image steganography on heavy traffic forums? I recall this is what North Korean spies used to do in early 2000s
- michaelt 2y ago
  > im not sure i understand what this means, can you provide an example and why its controversial? There is a longstanding tradition of vendors of mediocre 'security' systems using trade secrets/restrictive license terms/anti-hacking laws to cover up their mediocrity. If you're shopping for a garage door opener and one vendor publicly documents their security system and well known experts have given it their thumbs up, while another vendor says their system is secret and has sued people for attempting to reverse engineer it? Knowledgeable folk would have far more trust in the former than the latter.
  - localfirst 2y ago
    still dont get it. are you saying the former is susceptible to layering attacks where they get people to drop their guard? or that the latter which is secretive is to conceal its actual use
dllthomas 2y ago
> a one time pad is and will remain highly secure A one-time pad generated correctly and used correctly will remain highly secure, provided you have a highly secure means of sharing the key material. There's a lot rolled into those assumptions.
- bawolff 2y ago
  At the same time "highly secure" is significantly underselling it. One time pads (if properly implemented) are information-theoretically secure. Even if you solve P=NP your one time pad will not be cracked. It is safe against an adversary with both infinite time and infinite compute. That type of security comes at a cost.
  - dreamcompiler 2y ago
    And the cost is that one-time pads are a royal pain in the ass. But if you're willing to pay that price without cutting corners, you get a completely unbreakable crypto system that will laugh in the face of the NSA and quantum computers.
    - bawolff 2y ago
      In fairness, quantum doesn't really help against normal crypto (of the type that is being discussed - symmetric). AES-256 will also laugh in the face of QC.
      - dreamcompiler 2y ago
        Indeed. Quantum is only useful (in principle) against some types of asymmetric algorithms.
  - dllthomas 2y ago
    TBH, I think "highly secure" might be overselling it. Yes, assuming you're generating random numbers well, there's actually zero chance your security will be breached because of an attack on your encryption algorithm. But there's not actually zero chance that your random number generation is flawed, and (very much more important) the cost is in making harder the pieces of your system that are probably more likely to fail in the first place. And of course you're still potentially vulnerable to traffic analysis and such even if all the rest goes right.
pbronez 2y ago
A good example of #3 are public share links. Things are more secure if you share your file with a specific set of users, but that requires your counterpart to have an account with the system you’re using (eg a Google Account for Google Drive). When sharing files with an arbitrary counterparty, it’s often sufficient to generate a publicly available, unlisted/unindexed, hard to guess URL. Even better if it’s time boxed. I’m sure there are attackers who attempt to identify and enumerate these URLs. If they’re well designed though, it should be infeasible to guess the link.
- walterbell 2y ago
  > it’s often sufficient to generate a publicly available, unlisted/unindexed, hard to guess URL Unless a service is leaking or spidering the URL into a public index. https://positive.security/blog/urlscan-data-leaks https://positive.security/blog/urlscan-data-leaks https://arstechnica.com/information-technology/2014/05/dropbox-disables-old-shared-links-after-tax-returns-end-up-on-gooogle/ https://arstechnica.com/information-technology/2014/05/dropb... https://security.stackexchange.com/questions/239762/how-are-hidden-private-urls-being-leaked-to-third-parties https://security.stackexchange.com/questions/239762/how-are-...
- avidiax 2y ago
  https://gizmodo.com/cia-websites-reportedly-led-to-the-exposure-of-critical-1849601326 https://gizmodo.com/cia-websites-reportedly-led-to-the-expos... It is much harder than it would seem to keep these links secret. If one of your assets gets caught by other means, they could endanger the entire network if they use the same methodology. The CIA thought they had a super great system, and then many of their assets got rolled up at once in a hugely embarrassing (and deadly) blunder.

cqqxo4zV46cp 2y ago

The fact that 3 is controversial is telling of the sad state of the security knowledge of techies generally. The most people seem to be able to do is to cargo cult / parrot, misunderstand, and misappropriate quips like “security by obscurity bad!” when it, all else equal, is a perfectly reasonable and often useful additive measure to take if it’s available to you.

willis936 2y ago
You can even poke holes in it using their own terminology. Obscurity is equivalent to minimizing attack surface area. The less adversaries know about your system the smaller of a target it is.
- noduerme 2y ago
  I think there's overlap between surface area and obscurity, but they're not equivalent. To use the most pedestrian example, moving SSH off of port 22 makes it more obscure, but the total surface area hasn't gotten smaller.
  - thyrsus 2y ago
    Anecdata: log files with failed login attempts became far smaller after leaving port 22.
kibwen 2y ago
A knee-jerk aversion to anything halfway adjacent to "security by obscurity" is flawed, but this reaction to that aversion is also flawed. Instead of trying to suggest "security by obscurity is fine, actually, and don't worry about it", it's time for us to just stop being pithy and start being precise: your cryptosystem should be secure even if your adversaries understand everything about it. If that is true, then you can (and, in the real world, almost certainly should) add defense in depth by adding layers of obscurity, but not before.
chmod775 2y ago
> The most people seem to be able to do is to cargo cult / parrot, misunderstand, and misappropriate quips like “security by obscurity bad!" That is the point. It is a good rule of thumb for people who don't know much about security. Anything they create trying to add more security to their system is more likely to do the opposite. If you think you know better, feel free to ignore it. Just be aware you wouldn't be the first who thought they knew what they were doing or even the first who did know, yet still messed up.
ef32d2d 2y ago
Yeah. I think it's the result of conflating theoretical cryptography and practical IT security. Kerckhoffs's principle is true in the theoretical domain and it's certainly important that the designers of standardised crypto algorithms adhere to it but it doesn't follow that it's pointless to change your SSH port.
adrian_b 2y ago
While “security by obscurity” may be good for some spy agency as an additional layer over a system that would remain secure even if it were published, most people are right to say that “security by obscurity bad!”, based on the known history of such systems. The reason is that, without any exception, every time when some system that used “security by obscurity” has been reverse engineered, regardless if it was used for police communications, mobile phone communications, supposedly secure CPUs etc. it was discovered that those systems have been designed by incompetent amateurs or perhaps by competent but malevolent professionals, so that those systems could be easily broken by those who knew how they worked. “Security by obscurity” is fine for secret organizations, but for any commercial devices that incorporate functions that must be secure it is stupid for a buyer to accept any kind of “security by obscurity”, because that is pretty much guaranteed to be a scam, regardless how big and important the seller company is. Obscurity is OK only when it is added by the owner of the devices, over a system that is well known and which has been analyzed publicly.
Natsu 2y ago
This misunderstands how "security by obscurity" came about, because there are good and bad types of obscurity. Back in the 1800s people were selling shoddy locks that were easy to pick and they were mad that people were disclosing lock picking methods: https://www.okta.com/identity-101/security-through-obscurity/ https://www.okta.com/identity-101/security-through-obscurity... This history repeated later, with people making shoddy cryptography where they didn't want anyone to know how it worked, and similar things, most of which got broken in embarrassing ways. This sort of obscurity was actively harmful and let people sell defective products that people relied upon to their detriment. Meanwhile, there are good types of obscurity, too. For example, there are the information disclosure CWEs that tell users of products not to disclose version numbers, stack traces, etc. to users, and this sort of "obscurity" is perfectly reasonable and widely accepted. So it's not the case that all things that might be termed "obscurity" are bad.

localfirst 2y ago

" there are benefits to security by obscurity when its part of a layered approach with constant maintenance and feedback" im not sure i understand what this means, can you provide an example and why its controversial? do you mean a one time pad using memes via image steganography on heavy traffic forums? I recall this is what North Korean spies used to do in early 2000s

michaelt 2y ago
> im not sure i understand what this means, can you provide an example and why its controversial? There is a longstanding tradition of vendors of mediocre 'security' systems using trade secrets/restrictive license terms/anti-hacking laws to cover up their mediocrity. If you're shopping for a garage door opener and one vendor publicly documents their security system and well known experts have given it their thumbs up, while another vendor says their system is secret and has sued people for attempting to reverse engineer it? Knowledgeable folk would have far more trust in the former than the latter.
- localfirst 2y ago
  still dont get it. are you saying the former is susceptible to layering attacks where they get people to drop their guard? or that the latter which is secretive is to conceal its actual use

dllthomas 2y ago

> a one time pad is and will remain highly secure A one-time pad generated correctly and used correctly will remain highly secure, provided you have a highly secure means of sharing the key material. There's a lot rolled into those assumptions.

bawolff 2y ago
At the same time "highly secure" is significantly underselling it. One time pads (if properly implemented) are information-theoretically secure. Even if you solve P=NP your one time pad will not be cracked. It is safe against an adversary with both infinite time and infinite compute. That type of security comes at a cost.
- dreamcompiler 2y ago
  And the cost is that one-time pads are a royal pain in the ass. But if you're willing to pay that price without cutting corners, you get a completely unbreakable crypto system that will laugh in the face of the NSA and quantum computers.
  - bawolff 2y ago
    In fairness, quantum doesn't really help against normal crypto (of the type that is being discussed - symmetric). AES-256 will also laugh in the face of QC.
    - dreamcompiler 2y ago
      Indeed. Quantum is only useful (in principle) against some types of asymmetric algorithms.
- dllthomas 2y ago
  TBH, I think "highly secure" might be overselling it. Yes, assuming you're generating random numbers well, there's actually zero chance your security will be breached because of an attack on your encryption algorithm. But there's not actually zero chance that your random number generation is flawed, and (very much more important) the cost is in making harder the pieces of your system that are probably more likely to fail in the first place. And of course you're still potentially vulnerable to traffic analysis and such even if all the rest goes right.

pbronez 2y ago

A good example of #3 are public share links. Things are more secure if you share your file with a specific set of users, but that requires your counterpart to have an account with the system you’re using (eg a Google Account for Google Drive). When sharing files with an arbitrary counterparty, it’s often sufficient to generate a publicly available, unlisted/unindexed, hard to guess URL. Even better if it’s time boxed. I’m sure there are attackers who attempt to identify and enumerate these URLs. If they’re well designed though, it should be infeasible to guess the link.

walterbell 2y ago
> it’s often sufficient to generate a publicly available, unlisted/unindexed, hard to guess URL Unless a service is leaking or spidering the URL into a public index. https://positive.security/blog/urlscan-data-leaks https://positive.security/blog/urlscan-data-leaks https://arstechnica.com/information-technology/2014/05/dropbox-disables-old-shared-links-after-tax-returns-end-up-on-gooogle/ https://arstechnica.com/information-technology/2014/05/dropb... https://security.stackexchange.com/questions/239762/how-are-hidden-private-urls-being-leaked-to-third-parties https://security.stackexchange.com/questions/239762/how-are-...
avidiax 2y ago
https://gizmodo.com/cia-websites-reportedly-led-to-the-exposure-of-critical-1849601326 https://gizmodo.com/cia-websites-reportedly-led-to-the-expos... It is much harder than it would seem to keep these links secret. If one of your assets gets caught by other means, they could endanger the entire network if they use the same methodology. The CIA thought they had a super great system, and then many of their assets got rolled up at once in a hugely embarrassing (and deadly) blunder.