17 ms·

How Cloudflare blocked a monumental 7.3 Tbps DDoS attack

265 points by methuselah_in 1y ago

keygen_music 1y ago
[flagged]
londons_explore 1y ago
A DDoS gets some fraction of the entire internet to attack a single host. As the internet gets more users and more devices connected, the ratio of DDoS volume to a single connections volume will only get larger. Is there any kind of solution?
- alyandon 1y ago
  Not a 100% solution but would help greatly if ISPs: 1) performed egress filtering to prevent spoofing arbitrary source addresses 2) temporarily shut off customers that are sending a large volume of malicious traffic
  - dijit 1y ago
    Largely they do these things, it’s just not completely automatic.
  - alberth 1y ago
    > sending a large volume of malicious traffic How would an ISP determine egress is malicious? Genuinely curious.
    - markrages 1y ago
      https://www.ietf.org/rfc/rfc3514.txt https://www.ietf.org/rfc/rfc3514.txt
    - alyandon 1y ago
      If someone is reporting malicious traffic coming from the ISP's network then an ISP should be obligated to investigate and shut off the offending customer if necessary until they've resolved the problem.
      - cyral 1y ago
        How would this ever work at scale? These attacks come from thousands of compromised devices usually. e.g. Someone's smart fridge with 5 year old firmware gets exploited
        alyandon 1y ago
        I don't have a specific answer for that but it is really a problem that residential ISPs are going to have to solve now that gigabit or faster symmetric internet connections are becoming the norm.
        nhecker 1y ago
        As dijit (above this comment) has noted, this is somewhat possible and automated today. For example, one method has the attacked IP get completely null-routed, and the subsequent route is advertised. Upstream routers will pick up the null-route advertisement and drop the traffic ever closer to the source(s). The effect of the null route is that the attacked IP is unreachable by anyone until the null-route is lifted... so the aim of the DDoS isn't averted, but at least the flood of traffic won't pummel any network paths except for (ideally) the paths between the attacker(s) and the first router respecting the null-route. In my experience the DDoS tends to stop more quickly and shift away to other targets if the folks directing the attack can no longer reach the target (because: null-route) and then the null-route can be lifted sooner relative to a long-running DDoS that hasn't shifted away to other targets.
        whstl 1y ago
        With SMTP there are services who provide a list of malicious servers so that they can be blocked at the receiving end. I wonder if this would work in reverse, having a standardised, automated protocol that allow providers like Cloudflare to notify upstream networks of attacks in real time, so malicious traffic can be blocked closer to the source. Genuinely curious, I'm not an expert in low-level networking ops.
    - bityard 1y ago
      All large ISPs have fancy network visibility and DDoS mitigation solutions.[1] But getting them to actually USE them for problems that aren't lighting up their monitoring dashboards is another story entirely. (1. I know this, because I used to work for a company that made them, and the majority of worldwide ISPs were our customers.)
    - stackskipton 1y ago
      One simple way to do it is configure the customers routers to drop/reject all UDP/TCP packets where SRC address does not match Private IP/WAN Assigned Public IP.
      - Y_Y 1y ago
        The customer's router is for the customer to configure
        __turbobrew__ 1y ago
        I think ideally the customers router shouldn’t be touched, but the ISP can still do packet filtering on the next hop to drop any packets which don’t have a src ip matching the assigned WAN address of the router.
        pedrocr 1y ago
        Wouldn't that need a huge amount of extra hardware to do that filtering when the routers in each customer's home are mostly idle? Just setting egress filtering as the default and letting users override that if they need to for some reason should be a good outcome. The few that do change the default hopefully know what they are doing and won't end up part of a DDoS but they'll be few anyway so the impact will still be small.
        remram 1y ago
        The router in the customer's home cannot be trusted. With cable at least, you are able to bring in your own modem and router. Even if not, swapping it is easy, you just have to clone the original modem's MAC. In practice this is probably quite common to save money if nothing else (cable box rental is $10+/mo). Note that spoofing source IPs is only needed by the attacker in an amplification attack, not for the amplyfing devices and not for a "direct" botnet DDOS.
        SoftTalker 1y ago
    - zokier 1y ago
      Hundreds of Gbps of UDP traffic to random ports of a single destination IP from residental (?) network should be pretty easy pattern to automatically detect and throttle. More advanced attacks are more tricky to detect, but plain dumb UDP flood should be easily detectable.
      - quotemstr 1y ago
        > Hundreds of Gbps of UDP traffic to random ports of a single destination IP from residental (?) network You mean my legitimate QUIC file transfer?
        BenjiWiebe 1y ago
        Have you ever uploaded 100's of Gbps over QUIC from your residential connection to a single IP? And the aggregate across the ISP's network could in theory be monitored - so if you were uploading 1Gbps, yes, it could be legitimate. If you and 582 others were all uploading 1Gbps to the same IP at the same time, much less likely legitimate.
        quotemstr 1y ago
        > Have you ever uploaded 100's of Gbps over QUIC from your residential connection to a single IP? Yes actually --- migration between cloud bulk storage providers. Edit: I misread Gbps as Mbps above.
        zokier 1y ago
        Which residential ISP offers >100Gbps service?
        ongy 1y ago
        My homenet is 1GBit, so is my Internet I.e. no traffic beyond my legitimate saturation can reach the ISP I have saturated my link with quic or wireguard (logical or) plenty of times. The lack of any response on high data rates would be an indicator I've only tried that once and it failed gloriously due to congestion. I don't think there's many real protocols that are unidirectional without even ACKs
- sybercecurity 1y ago
  Apparently no solution that has gained traction, and no single solution that works everywhere. Source address filtering (BCP 38) got us part of the way, but it's difficult/undesired to do in data centers. IoT devices (speculated to be used here) would have to have a solution upstream. Things like MUD (RFC 8520) have been proposed, but have problems too - developers need to be able to list all communications of their device and make that available somehow (MUD profile server). Some consumers will never do it on their own, and may want to prevent alerting a device manufacturer they have a device (think connected adult toy...). Also given that IoT devices may never be updated by their owners, expect to see IoT botnet DoS attacks for years.
  - citrin_ru 1y ago
    > Source address filtering (BCP 38) got us part of the way, but it's difficult/undesired to do in data centers. BCP 38 is applicable in the DC environment, especially between an operator (hosting/cloud provider) and the customer. Where it is from hard to not practical to use is the network backbone and link between different ISPs. But that's would be a minor problem if BCP 38 will be applied to all stub networks.
- resource_waste 1y ago
  Capachas? Sorry for the worst and most hated possible solution, but I thought I'd at least mention it. Maybe too many failed capachas causes you to not connect to the IP for an hour.
  - tliltocatl 1y ago
    How would you expect capachas to help against UDP flood? The attack works by oversaturating the network channel. Capachas is a (terribly bad) solution to prevent the server from spending CPU and transmit bandwidth on garbage request, but these wouldn't do anything if the server have too much packets receive in the first place.
    - Zambyte 1y ago
      TIL about capachas[1] [1]: https://en.wikipedia.org/wiki/Cachapa https://en.wikipedia.org/wiki/Cachapa
      - BenjiWiebe 1y ago
        Capacha =/= Cachapa =/= CAPTCHA
- blueflow 1y ago
  Make people pay per traffic.
  - loloquwowndueo 1y ago
    We already do. Attackers use stolen capacity.
    - blueflow 1y ago
      But why doesn't the market do the market thing, then?
      - viraptor 1y ago
        For each separate endpoint the impact is minimal. Being part of the attack would cost you an extra $1 and you wouldn't even notice. On the other hand, ensuring the metering works correctly, reporting to the billing system works, invoicing it properly, providing support, etc. likely costs more per-customer.
- ByThyGrace 1y ago
  Consumer home/office routers provide their clients IP connectivity without reserve. Why is that the case? The default is to allow all available bandwidth, which presumably should be the case from ISP to consumer (most likely a paid-for service), but why should that be the default at consumer router <-> IoT? What need has your printer for 500Mbps outgoing? Or my fancy toothbrush?
  - shermantanktop 1y ago
    Is there any method for a connected device to advertise the required throughput? Maybe some SNMP thing? That’s the only way this would work I think.
    - BenjiWiebe 1y ago
      You would want the advertised speed to be approved by the user at the time of setup. If it was automatically accepted, the malware would just change the advertisement.
    - everforward 1y ago
      Users don't want to manage it, and ISPs don't want the tickets. Heuristic based systems would probably work in most homes, where devices are limited by their historical bandwidth. New devices are unthrottled, existing devices are limited by their historical bandwidth usage with some bursting. I think most ISPs have apps to control your router now, you could have it trigger a push notification like "Device X is using more bandwidth than normal, and we're throttling it. Press SCARY BUTTON to unthrottle."
  - ryandrake 1y ago
    Residential ISPs need to better police abuse of the network and they need to better respond to reports of abuse by cutting off the abusive, botnet-infected users. Of course, until there is a financial or regulatory incentive to cut off these customers, they won’t.
- pfdietz 1y ago
  Locate and brick IoT devices with vulnerabilities?
  - lofaszvanitt 1y ago
    Good idea. People only learn that something is wrong, when... they don't have internet anymore ;D.
- toast0 1y ago
  > As the internet gets more users and more devices connected, the ratio of DDoS volume to a single connections volume will only get larger. I'm not sure if that's the case. Large volumetric DDoS records have been increasing, but connection bandwidths have also been increasing. 7 tbps is a lot of traffic, but it only takes 7,000 nodes with 1G symetric connections to do it. Botnet sizes don't seem to be getting that much bigger. The basic solution to volumetric DDoS is to get a bigger pipe; this works, kind of, but it's hard to get 7 Tbps of downstream capacity, and you need to be careful that you don't become a 7 Tbps reflector. The more scalable way is using BGP to drop traffic before it gets to you. Depending on your relationship with your hosting facility and their ISPs or your ISPs, it's often pretty easy to get packet to a given IP dropped one network before yours. Ocassionally, those blocks could propagate, and things like BGP Flow Spec promise more specific filtering... dropping all packets to an attacked IP mitigages the attack for the rest of the IPs on the path, but dropping all UDP to an attacked IP might get all the attack traffic and let most non-attack traffic through... More specific rules are possible if you wanted to try to let DNS and HTTP/3 survive while being attacked. To work against a 45 second attack, BGP based measures need a lot of automation.
  - deleted 1y ago
    [deleted]
  - dale_huevo 1y ago
    You don't think the proliferation of inexpensive dogshit IoT products from the Far East, running already-10-years-out-of-date versions of Linux (bonus if it has a hidden Telnet daemon with hardcoded root password!), hooked to ever-expanding 1Gbps residential fibre lines, has anything to do with it? This represents like 75% of surveillance camera systems out there btw.
    - toast0 1y ago
      I think the increase in 1G residential connections is a bigger factor than the IoShit products. I don't think botnet node counts are getting that much bigger, but the amount of garbage each one can push certainly is.
- franga2000 1y ago
  Banks have already figured out fraud detection through pattern recognition, ISPs can do the same. When a connection has never used more than 300/10 of a 1000/1000 link and 80% of that was TCP with dstport 80 or 443, then it starts doing /900 UDP to every possible dstport, maybe something is wrong? "Your network is generating an extraordinary amout of traffic, which is likely the result of a virus-infected device. As a result, we have lowered your speed to 100/20. Please read the steps to check your devices and unlock your connection here: ____"
  - itake 1y ago
    Banks have way lower traffic and slower reaction times than what cf needs to support. Lowering the speed means "good" traffic is also impacted, resulting in higher timeouts. count the number of events isn't cheap either.
  - overfeed 1y ago
    IoS botnets depend on total number of devices and not individual bandwidth. Most IoT devices have cheap network chipsets and unoptimized networking stacks, I wouldn't expect them to saturate a 100mbps connection.
  - xyst 1y ago
    So many false positives can happen here. Most ISPs are already a pain in the ass to deal with. (Fuck you Charter/Spectrum). I don’t trust them to do their due diligence and implement this correctly. Or worse, abuse it. “hey you pay for 1000/300 package. We detected abnormal traffic. Now you get throttled to 100/100. But still pay 1000/30”. Then they will drag on the resolution process until you give up.
  - orlp 1y ago
    Economic fraud detection is like trying to find a needle in a haystack. Blocking DDoS is like trying to separate the shit from the bread in a shit sandwich. It's a completely different problem.
losthobbies 1y ago
Dodgy IoT devices will be the end of us all.
- bearjaws 1y ago
  It's wild to think with the proliferation of 1gbps fiber internet, even a modern pi board or old desktop is a potential 1gbps bot host.
  - dinkblam 1y ago
    [flagged]
  - franga2000 1y ago
    When your IP is found to have been part of a botnet, I think ISPs should just limit you to like 20Mbps for at least a year, so you think twice about buying that 10$ wifi baby monitor next time.
    - bogdan 1y ago
      That's quite harsh. Good thing you're not in charge of making decisions.
      - deleted 1y ago
        [deleted]
      - mschuster91 1y ago
        When you get caught speeding on the road or being a nuisance otherwise you can and will get punished by the courts, including temporary restrictions on your driver license. When you money mule for others, even if you don't know that you actually fell victim to a scam, you get punished as well. When you litter in Singapore, you can get ordered to work community service. I see no issue in handing out similar punishments in the digital space. The Internet is a shared medium, everyone who connects to it has a responsibility to not be a nuisance to others.
8e0a9dc477a9ded 1y ago
[flagged]
shrubble 1y ago
The current optics are 400gbps, and 800gbps are sampling; next up is 1.6 tbps; so this is 20x400gbps, basically 1 expensive switch’s worth of traffic. Which is itself a scary prospect!
- immibis 1y ago
  It's cloudflare so it's distributed. 10Gbps at this POP, 20Gbps at that one...
thih9 1y ago
> DDoS sizes have continued a steady climb over the past three decades. This is a bit misleading; according to Wikipedia[1], the first DDoS is said to have occurred less than three decades ago. [1] "Panix, the third-oldest ISP in the world, was the target of what is thought to be the first DoS attack. On September 6, 1996, Panix was subject to a SYN flood attack, which brought down its services for several days while hardware vendors, notably Cisco, figured out a proper defense.", source: https://en.wikipedia.org/wiki/Denial-of-service_attack https://en.wikipedia.org/wiki/Denial-of-service_attack
- sophacles 1y ago
  So the change from 0 sized ddos in June 1995 (30 years ago aka 3 decades ago) to a >0 sized ddos in September 1996 (29 years ago aka basically 3 decades ago) doesn't constitute an increase in size?
  - thih9 1y ago
    But that’s my point, I wouldn’t call it an increase from 0, I’d say 30 years ago that value was NULL - not even a zero sized DDoS has happened yet.
    - sophacles 1y ago
      So two problems... 1) I'm not sure what your problem with the reasonable rounding of 29 years ago to 3 decades is... but the one that comes across is "extra pedantry for no reason" 2) According to wikipedia the "first dos" attack was in 1996. There are other sources most of which attribute that 1996 panix attack as "one of the first" or "the first major" ddos attack. Before that there were other DoS attacks using udp and/or syn floods, and some of them likely involved several computers (and possibly people) working in coordination. Those several computers were probably not compromised machines that had malware responding to a cnc server, so the squishiness has to do in part with how exactly one defines DDoS - some definitions include a botnet requirement, others just need multiple computers working in coordination. It's claimed that Kevin Mitnick was targeting his prosecutor with syn floods in 1994 (over 30 years ago), but its not fully verified and the details are unknown from my research... likely though >1 computers were involved in that flood if it happened. In the early 90s there were all sorts of fun and games where people would knock over IRC servers by triggering bugs/behaviors in a lot of connected clients. It's primitive but it seems to have a huge number of elements of DDoS. Similar for attacks on various telecomms infrastructure as the soviet union/eastern bloc fell apart in that time period. Trying to put a hard "29 years ago" line in the sand is difficult to do... techniques evolve from previous ones and there are shared elements that make the line necessarily fuzzy. So yeah... theres no reason to quibble about "three decades" since theres 35+ years of history around "things that look like DDoS attacks but don't fit a strict definition that requires botnets"
jakub_g 1y ago
> QOTD DDoS attack > How it works: Abuses the Quote of the Day (QOTD) Protocol, which listens on UDP port 17 and responds with a short quote or message. Does any reasonable operating system those days support this protocol? Sounds like "IP over Avian Carriers" to me.
- unilynx 1y ago
  They're not an April fool's joke. A 90's linux might have these services enabled by default. I assume they were built to make network debugging slightly less boring
  - skeezyboy 1y ago
    [dead]
- toast0 1y ago
  Is it part of Microsoft Services for Unix? That seemed to be the primary source of chargen reflectors when I was getting hit by that; and it feels like a similar thing.
- NoboruWataya 1y ago
  Huh, this sounds kind of cool, I like the idea of there being a few QOTD servers dotted around the internet. Shame that the first I'm heading about it is it being abused to launch a DDOS.
  - msgodel 1y ago
    You can always ssh to random hosts and read the netbanners. Of course nearly all of them are a long paragraph or two of legal jargon that more or less boils down to "fuck off."
    - Retr0id 1y ago
      SSH banners come over TCP, requiring the 3-way handshake first, meaning you can't use it for traffic reflection (beyond the SYN-ACK itself).
wrs 1y ago
What was the goal of an attack lasting only 45 seconds?
- dylan604 1y ago
  Maybe someone was interested in buying the services, and the creator need to prove the capabilities. I'm sure there's other reasons too.
- dc396 1y ago
  A few options: - testing in preparation for a future attack - proof of capability ("Nice network you have there. It'd be a shame if something happened to it") - misfire ('What happens when I push this button that says "don't push"?')
- mxuribe 1y ago
  I was thinking reconn...but the other reasons cited by others here seem totally viable too.
NetOpWibby 1y ago
Cloudflare is the One Punch Man of the internet
- johnklos 1y ago
  Cloudflare protects scammers and want to recentralize the Internet around a for-profit company based in the Untied States. One-Punch Man is a reluctant mentor, is often broke, loves ramen and cares about others. They are not the same.
pariainterpares 1y ago
Any proof that this happened except cloudflare claiming it did? Just wondering whether these kind of attacks are seen by other orgs.
slt2021 1y ago
L4 level ddos is useless and is easily protected by Cloudflare. App level DOS use Cloudflare evasion techniques and directly DOS the destination server, while keeping itself undetected by Cloudflare's systems. Do not assume that Cloudflare will protect you from all attacks, if your app is dogshit python/js/php then even cloudflare wont protect you from L7 DDOS
deleted 1y ago
[deleted]
ripberge 1y ago
Huh, I got attacked from 170 countries last year (HTTP) and Cloudflare's autonomous detection (machine learning powered) rules did almost nothing. It was millions of the same requests over and over and the only thing that we could do to stop it was manually put in rules to block routes. Not only that, some of the attacking traffic came from within Cloudflare workers or it was at least going through their WARP client (those details are now fuzzy). Was a pretty miserable failure to perform on their part.
- reassess_blind 1y ago
  How many requests per second?
- pacalleri 1y ago
  Similar experience last week. But tbh I'm using the free plan so I wasn't expecting too much from them. What it worked was to use nginx rate limiter aggressively, parse logs and deny top ips with nginx. Because all traffic comes through CF I wasn't able to use iptables for blocking
  - reassess_blind 1y ago
    Cloudflare’s has a free rate limit feature, btw. Not as configurable as nginx but it’s nice to not have the requests touch your server at all.
  - hombre_fatal 1y ago
    If you can thwart it with your own nginx, then it can’t be much of an attack. Cloudflare is one of your only hopes against a volumetric attack especially when paying $0.
knowitnone 1y ago
Should Cloudflare release the IPs and try to get those devices removed from the internet?
- _alternator_ 1y ago
  That would just be a target list for hackers. Most of the devices that take part are going to be in homes or SMBs with old firmware that’s subject to known vulnerabilities. They will give the list to AS operators who request the offending IPs (presumably restricted to the AS ranges) but dropping it out on the public internet just invites trouble.
- mschuster91 1y ago
  They could but it's whack-a-mole and most ISPs just route abuse reports straight to /dev/null. IMHO, ISPs caught in that act should get yanked off the internet.
- miyuru 1y ago
  they do for ISPs who wants to do it. this is referred in the "Free botnet threat feed" of the article.
- AtNightWeCode 1y ago
  Not sure about CF but a lot of corps report to https://www.abuseipdb.com https://www.abuseipdb.com. So it is not hard to get the IPs of attackers.
dangoodmanUT 1y ago
It almost feels like writing about this is exactly what the attacker wants: Free validation and advertisement for exactly what their botnet can do
- creatonez 1y ago
  Is this a sign that A: Cloudflare is feeding the trolls because they think that they are invincible. Or: These post-mortems don't establish any proof that the attack was successful, especially if they are covering DDoSes that were barely even noticed by the public until CF publishes a blog post 1 month later -- so it's actually embarrassing for them and hurts their ability to market botnets for rent, at least once they no longer have the literal world record. B: Cloudflare is feeding the trolls for free testing scenarios to improve the mitigation C: The trolls don't really care if you feed them, large DDoS is something that's happening all the time anyways
  - kevindamm 1y ago
    D: all of the above
  - motorest 1y ago
    > Is this a sign that Isn't the obvious point that this is Cloudflare advertising their anti-DDoS services?
- v5v3 1y ago
  But now the ip's of their botnet are known, the bot net is weakened. Also it makes no sense - why throw 7.3tbps at a server, when half of that or less would have the same effect and not exposed your botnet.
m463 1y ago
meanwhile, cloudflare has been blocking my reading of websites more and more.
yamapikarya 1y ago
i just depends on waf, as long as the ddos attack does not reach my server. is that ok?
AngryData 1y ago
Sort of neat, but also feels like this post is 95% marketing and PR because its just a cherry picked example of success.
codedokode 1y ago
The main problem is that there is no "STOP" protocol, where you can send a packet indicating that you do not want to receive traffic from given AS or IP. Or at least that you are not going to pay for it. I think we need to support blocking at least on /24 prefix level.
kevmo314 1y ago
This article taught be about the QOTD protocol: https://datatracker.ietf.org/doc/html/rfc865 https://datatracker.ietf.org/doc/html/rfc865 Cool artifact of the internet!
- jkingsman 1y ago
  I run it inside my private network because it's cute. I wrote a toy C utility and made it Docker-friendly so I could just toss it at proxmox. https://github.com/jkingsman/RFC865-QotD-Server-for-Docker https://github.com/jkingsman/RFC865-QotD-Server-for-Docker
victorstanciu 1y ago
@tete called it: https://news.ycombinator.com/item?id=44262324 https://news.ycombinator.com/item?id=44262324
- haxton 1y ago
  Unrelated. Has nothing to do with the gcp outage that was related to.
- esseph 1y ago
  No, this is old.
  - esseph 1y ago
    Oops - My mistake, this is not the attack that got stopped earlier this year that broke the previous record.
lordnacho 1y ago
Possibly the only kind of advertising that I actually like. Informative, engaging, no overselling.
candiddevmike 1y ago
What does this botnet do when it's not performing a 7.3 Tbps DDoS? Yea it's probably regular folks computers, but what "wakes up" the botnet to attack? What makes an attack target worthwhile? Presumably something this large would be on someone's radar...
- jamessinghal 1y ago
  The Command-and-Control part of the botnet would be whatever component they build to instruct it to attack; often using some dummy website they register and have the compromised clients poll for changes with instructions. I think an increasing amount of them are state actors or groups offering the botnet as a service.
  - esseph 1y ago
    also add in DNS fastflux https://www.cisa.gov/news-events/cybersecurity-advisories/aa25-093a https://www.cisa.gov/news-events/cybersecurity-advisories/aa... https://www.cloudflare.com/learning/dns/dns-fast-flux/ https://www.cloudflare.com/learning/dns/dns-fast-flux/
- toast0 1y ago
  I mean... 7 Tbps sounds like a lot, but 1Gbps symetric connections are common in many areas. 7,000 botnet nodes with good connectivity can deliver that. The article says the attack traffic came from 122,145 source IPs, but I would expect at least some traffic to be spoofed.
- rasz 1y ago
  >What does this botnet do when it's not performing a 7.3 Tbps DDoS? Living their best "Im a retail Asus router/iot from Amazon" life.
password4321 1y ago
← Inserting standard complaint about Cloudflare protecting the sites selling these DDoS attacks here (at best: a conflict of interest selling the cure while protecting the disease).
- jonathanlydall 1y ago
  How does CloudFlare protect the disease? Also worth noting that the article specifically mentions how owners of ASNs can subscribe to CloudFlare at no charge to get notified when devices on their network are participating in attacks like this.
  - Spivak 1y ago
    I think by treating the symptom they end up making it so that people don't actually do anything of substance in response to these absolutely massive attacks. Just put your site behind Cloudflare, obviously. Problems solved. Why do we need to do anything else?
  - password4321 1y ago
    > Cloudflare protect[s] the sites selling these DDoS attacks Not a new problem per https://krebsonsecurity.com/2014/02/the-new-normal-200-400-gbps-ddos-attacks/ https://krebsonsecurity.com/2014/02/the-new-normal-200-400-g... a funny thing happens when you decide to operate a DDoS-for-hire Web service: Your service becomes the target of attacks from competing DDoS-for-hire services. Hence, a majority of these services have chosen to avail themselves of Cloudflare’s free content distribution service
sparrish 1y ago
Anybody know who the "Cloudflare customer, a hosting provider" was and what IP they were targeting and why? I'm curious why someone would go to such great lengths to try to take down a service.
- porkloin 1y ago
  I don't know who the provider is, but the attack was almost certainly not targeting the provider, but a site hosted on their platform. Many hosting companies upsell their customers into stuff like providing Cloudflare DDoS prevention. The target site was probably something political or controversial. I work at a hosting provider and we deal with this type of thing constantly.
  - overfeed 1y ago
    > The target site was probably something political or controversial. Since this is Cloudflare, my headcanon is that it was a rival DDOS service, after a wild flamewar on some .ru hacker forum.
- toast0 1y ago
  The article says it was a 45 second attack. I used to run a high profile website which used to get a lot of 90 second attacks. Best I could figure was some of the ddos as a services would give a short attack as a free sample, and people picked us cause we were high profile. Thankfully, these would almost always attack our website rather than our service, and availability for our website didn't really matter. Most of the attacks weren't a big deal, and they'd get bored and move on to something else. The ones that did take a web server down were kind of nice... I could use those to tune both the webservers and the servers doing real work.

265 points by methuselah_in 1y ago

[flagged]

A DDoS gets some fraction of the entire internet to attack a single host. As the internet gets more users and more devices connected, the ratio of DDoS volume to a single connections volume will only get larger. Is there any kind of solution?

alyandon 1y ago
Not a 100% solution but would help greatly if ISPs: 1) performed egress filtering to prevent spoofing arbitrary source addresses 2) temporarily shut off customers that are sending a large volume of malicious traffic
- dijit 1y ago
  Largely they do these things, it’s just not completely automatic.
- alberth 1y ago
  > sending a large volume of malicious traffic How would an ISP determine egress is malicious? Genuinely curious.
  - markrages 1y ago
    https://www.ietf.org/rfc/rfc3514.txt https://www.ietf.org/rfc/rfc3514.txt
  - alyandon 1y ago
    If someone is reporting malicious traffic coming from the ISP's network then an ISP should be obligated to investigate and shut off the offending customer if necessary until they've resolved the problem.
    - cyral 1y ago
      How would this ever work at scale? These attacks come from thousands of compromised devices usually. e.g. Someone's smart fridge with 5 year old firmware gets exploited
      - alyandon 1y ago
        I don't have a specific answer for that but it is really a problem that residential ISPs are going to have to solve now that gigabit or faster symmetric internet connections are becoming the norm.
      - nhecker 1y ago
        As dijit (above this comment) has noted, this is somewhat possible and automated today. For example, one method has the attacked IP get completely null-routed, and the subsequent route is advertised. Upstream routers will pick up the null-route advertisement and drop the traffic ever closer to the source(s). The effect of the null route is that the attacked IP is unreachable by anyone until the null-route is lifted... so the aim of the DDoS isn't averted, but at least the flood of traffic won't pummel any network paths except for (ideally) the paths between the attacker(s) and the first router respecting the null-route. In my experience the DDoS tends to stop more quickly and shift away to other targets if the folks directing the attack can no longer reach the target (because: null-route) and then the null-route can be lifted sooner relative to a long-running DDoS that hasn't shifted away to other targets.
      - whstl 1y ago
        With SMTP there are services who provide a list of malicious servers so that they can be blocked at the receiving end. I wonder if this would work in reverse, having a standardised, automated protocol that allow providers like Cloudflare to notify upstream networks of attacks in real time, so malicious traffic can be blocked closer to the source. Genuinely curious, I'm not an expert in low-level networking ops.
  - bityard 1y ago
    All large ISPs have fancy network visibility and DDoS mitigation solutions.[1] But getting them to actually USE them for problems that aren't lighting up their monitoring dashboards is another story entirely. (1. I know this, because I used to work for a company that made them, and the majority of worldwide ISPs were our customers.)
  - stackskipton 1y ago
    One simple way to do it is configure the customers routers to drop/reject all UDP/TCP packets where SRC address does not match Private IP/WAN Assigned Public IP.
    - Y_Y 1y ago
      The customer's router is for the customer to configure
      - __turbobrew__ 1y ago
        I think ideally the customers router shouldn’t be touched, but the ISP can still do packet filtering on the next hop to drop any packets which don’t have a src ip matching the assigned WAN address of the router.
        pedrocr 1y ago
        Wouldn't that need a huge amount of extra hardware to do that filtering when the routers in each customer's home are mostly idle? Just setting egress filtering as the default and letting users override that if they need to for some reason should be a good outcome. The few that do change the default hopefully know what they are doing and won't end up part of a DDoS but they'll be few anyway so the impact will still be small.
        remram 1y ago
        The router in the customer's home cannot be trusted. With cable at least, you are able to bring in your own modem and router. Even if not, swapping it is easy, you just have to clone the original modem's MAC. In practice this is probably quite common to save money if nothing else (cable box rental is $10+/mo). Note that spoofing source IPs is only needed by the attacker in an amplification attack, not for the amplyfing devices and not for a "direct" botnet DDOS.
        SoftTalker 1y ago
  - zokier 1y ago
    Hundreds of Gbps of UDP traffic to random ports of a single destination IP from residental (?) network should be pretty easy pattern to automatically detect and throttle. More advanced attacks are more tricky to detect, but plain dumb UDP flood should be easily detectable.
    - quotemstr 1y ago
      > Hundreds of Gbps of UDP traffic to random ports of a single destination IP from residental (?) network You mean my legitimate QUIC file transfer?
      - BenjiWiebe 1y ago
        Have you ever uploaded 100's of Gbps over QUIC from your residential connection to a single IP? And the aggregate across the ISP's network could in theory be monitored - so if you were uploading 1Gbps, yes, it could be legitimate. If you and 582 others were all uploading 1Gbps to the same IP at the same time, much less likely legitimate.
        quotemstr 1y ago
        > Have you ever uploaded 100's of Gbps over QUIC from your residential connection to a single IP? Yes actually --- migration between cloud bulk storage providers. Edit: I misread Gbps as Mbps above.
        zokier 1y ago
        Which residential ISP offers >100Gbps service?
        ongy 1y ago
        My homenet is 1GBit, so is my Internet I.e. no traffic beyond my legitimate saturation can reach the ISP I have saturated my link with quic or wireguard (logical or) plenty of times. The lack of any response on high data rates would be an indicator I've only tried that once and it failed gloriously due to congestion. I don't think there's many real protocols that are unidirectional without even ACKs
sybercecurity 1y ago
Apparently no solution that has gained traction, and no single solution that works everywhere. Source address filtering (BCP 38) got us part of the way, but it's difficult/undesired to do in data centers. IoT devices (speculated to be used here) would have to have a solution upstream. Things like MUD (RFC 8520) have been proposed, but have problems too - developers need to be able to list all communications of their device and make that available somehow (MUD profile server). Some consumers will never do it on their own, and may want to prevent alerting a device manufacturer they have a device (think connected adult toy...). Also given that IoT devices may never be updated by their owners, expect to see IoT botnet DoS attacks for years.
- citrin_ru 1y ago
  > Source address filtering (BCP 38) got us part of the way, but it's difficult/undesired to do in data centers. BCP 38 is applicable in the DC environment, especially between an operator (hosting/cloud provider) and the customer. Where it is from hard to not practical to use is the network backbone and link between different ISPs. But that's would be a minor problem if BCP 38 will be applied to all stub networks.
resource_waste 1y ago
Capachas? Sorry for the worst and most hated possible solution, but I thought I'd at least mention it. Maybe too many failed capachas causes you to not connect to the IP for an hour.
- tliltocatl 1y ago
  How would you expect capachas to help against UDP flood? The attack works by oversaturating the network channel. Capachas is a (terribly bad) solution to prevent the server from spending CPU and transmit bandwidth on garbage request, but these wouldn't do anything if the server have too much packets receive in the first place.
  - Zambyte 1y ago
    TIL about capachas[1] [1]: https://en.wikipedia.org/wiki/Cachapa https://en.wikipedia.org/wiki/Cachapa
    - BenjiWiebe 1y ago
      Capacha =/= Cachapa =/= CAPTCHA
blueflow 1y ago
Make people pay per traffic.
- loloquwowndueo 1y ago
  We already do. Attackers use stolen capacity.
  - blueflow 1y ago
    But why doesn't the market do the market thing, then?
    - viraptor 1y ago
      For each separate endpoint the impact is minimal. Being part of the attack would cost you an extra $1 and you wouldn't even notice. On the other hand, ensuring the metering works correctly, reporting to the billing system works, invoicing it properly, providing support, etc. likely costs more per-customer.
ByThyGrace 1y ago
Consumer home/office routers provide their clients IP connectivity without reserve. Why is that the case? The default is to allow all available bandwidth, which presumably should be the case from ISP to consumer (most likely a paid-for service), but why should that be the default at consumer router <-> IoT? What need has your printer for 500Mbps outgoing? Or my fancy toothbrush?
- shermantanktop 1y ago
  Is there any method for a connected device to advertise the required throughput? Maybe some SNMP thing? That’s the only way this would work I think.
  - BenjiWiebe 1y ago
    You would want the advertised speed to be approved by the user at the time of setup. If it was automatically accepted, the malware would just change the advertisement.
  - everforward 1y ago
    Users don't want to manage it, and ISPs don't want the tickets. Heuristic based systems would probably work in most homes, where devices are limited by their historical bandwidth. New devices are unthrottled, existing devices are limited by their historical bandwidth usage with some bursting. I think most ISPs have apps to control your router now, you could have it trigger a push notification like "Device X is using more bandwidth than normal, and we're throttling it. Press SCARY BUTTON to unthrottle."
- ryandrake 1y ago
  Residential ISPs need to better police abuse of the network and they need to better respond to reports of abuse by cutting off the abusive, botnet-infected users. Of course, until there is a financial or regulatory incentive to cut off these customers, they won’t.
pfdietz 1y ago
Locate and brick IoT devices with vulnerabilities?
- lofaszvanitt 1y ago
  Good idea. People only learn that something is wrong, when... they don't have internet anymore ;D.
toast0 1y ago
> As the internet gets more users and more devices connected, the ratio of DDoS volume to a single connections volume will only get larger. I'm not sure if that's the case. Large volumetric DDoS records have been increasing, but connection bandwidths have also been increasing. 7 tbps is a lot of traffic, but it only takes 7,000 nodes with 1G symetric connections to do it. Botnet sizes don't seem to be getting that much bigger. The basic solution to volumetric DDoS is to get a bigger pipe; this works, kind of, but it's hard to get 7 Tbps of downstream capacity, and you need to be careful that you don't become a 7 Tbps reflector. The more scalable way is using BGP to drop traffic before it gets to you. Depending on your relationship with your hosting facility and their ISPs or your ISPs, it's often pretty easy to get packet to a given IP dropped one network before yours. Ocassionally, those blocks could propagate, and things like BGP Flow Spec promise more specific filtering... dropping all packets to an attacked IP mitigages the attack for the rest of the IPs on the path, but dropping all UDP to an attacked IP might get all the attack traffic and let most non-attack traffic through... More specific rules are possible if you wanted to try to let DNS and HTTP/3 survive while being attacked. To work against a 45 second attack, BGP based measures need a lot of automation.
- deleted 1y ago
  [deleted]
- dale_huevo 1y ago
  You don't think the proliferation of inexpensive dogshit IoT products from the Far East, running already-10-years-out-of-date versions of Linux (bonus if it has a hidden Telnet daemon with hardcoded root password!), hooked to ever-expanding 1Gbps residential fibre lines, has anything to do with it? This represents like 75% of surveillance camera systems out there btw.
  - toast0 1y ago
    I think the increase in 1G residential connections is a bigger factor than the IoShit products. I don't think botnet node counts are getting that much bigger, but the amount of garbage each one can push certainly is.
franga2000 1y ago
Banks have already figured out fraud detection through pattern recognition, ISPs can do the same. When a connection has never used more than 300/10 of a 1000/1000 link and 80% of that was TCP with dstport 80 or 443, then it starts doing /900 UDP to every possible dstport, maybe something is wrong? "Your network is generating an extraordinary amout of traffic, which is likely the result of a virus-infected device. As a result, we have lowered your speed to 100/20. Please read the steps to check your devices and unlock your connection here: ____"
- itake 1y ago
  Banks have way lower traffic and slower reaction times than what cf needs to support. Lowering the speed means "good" traffic is also impacted, resulting in higher timeouts. count the number of events isn't cheap either.
- overfeed 1y ago
  IoS botnets depend on total number of devices and not individual bandwidth. Most IoT devices have cheap network chipsets and unoptimized networking stacks, I wouldn't expect them to saturate a 100mbps connection.
- xyst 1y ago
  So many false positives can happen here. Most ISPs are already a pain in the ass to deal with. (Fuck you Charter/Spectrum). I don’t trust them to do their due diligence and implement this correctly. Or worse, abuse it. “hey you pay for 1000/300 package. We detected abnormal traffic. Now you get throttled to 100/100. But still pay 1000/30”. Then they will drag on the resolution process until you give up.
- orlp 1y ago
  Economic fraud detection is like trying to find a needle in a haystack. Blocking DDoS is like trying to separate the shit from the bread in a shit sandwich. It's a completely different problem.

losthobbies 1y ago

Dodgy IoT devices will be the end of us all.

bearjaws 1y ago
It's wild to think with the proliferation of 1gbps fiber internet, even a modern pi board or old desktop is a potential 1gbps bot host.
- dinkblam 1y ago
  [flagged]
- franga2000 1y ago
  When your IP is found to have been part of a botnet, I think ISPs should just limit you to like 20Mbps for at least a year, so you think twice about buying that 10$ wifi baby monitor next time.
  - bogdan 1y ago
    That's quite harsh. Good thing you're not in charge of making decisions.
    - deleted 1y ago
      [deleted]
    - mschuster91 1y ago
      When you get caught speeding on the road or being a nuisance otherwise you can and will get punished by the courts, including temporary restrictions on your driver license. When you money mule for others, even if you don't know that you actually fell victim to a scam, you get punished as well. When you litter in Singapore, you can get ordered to work community service. I see no issue in handing out similar punishments in the digital space. The Internet is a shared medium, everyone who connects to it has a responsibility to not be a nuisance to others.

8e0a9dc477a9ded 1y ago

[flagged]

shrubble 1y ago

The current optics are 400gbps, and 800gbps are sampling; next up is 1.6 tbps; so this is 20x400gbps, basically 1 expensive switch’s worth of traffic. Which is itself a scary prospect!

immibis 1y ago
It's cloudflare so it's distributed. 10Gbps at this POP, 20Gbps at that one...

thih9 1y ago

> DDoS sizes have continued a steady climb over the past three decades. This is a bit misleading; according to Wikipedia[1], the first DDoS is said to have occurred less than three decades ago. [1] "Panix, the third-oldest ISP in the world, was the target of what is thought to be the first DoS attack. On September 6, 1996, Panix was subject to a SYN flood attack, which brought down its services for several days while hardware vendors, notably Cisco, figured out a proper defense.", source: https://en.wikipedia.org/wiki/Denial-of-service_attack https://en.wikipedia.org/wiki/Denial-of-service_attack

sophacles 1y ago
So the change from 0 sized ddos in June 1995 (30 years ago aka 3 decades ago) to a >0 sized ddos in September 1996 (29 years ago aka basically 3 decades ago) doesn't constitute an increase in size?
- thih9 1y ago
  But that’s my point, I wouldn’t call it an increase from 0, I’d say 30 years ago that value was NULL - not even a zero sized DDoS has happened yet.
  - sophacles 1y ago
    So two problems... 1) I'm not sure what your problem with the reasonable rounding of 29 years ago to 3 decades is... but the one that comes across is "extra pedantry for no reason" 2) According to wikipedia the "first dos" attack was in 1996. There are other sources most of which attribute that 1996 panix attack as "one of the first" or "the first major" ddos attack. Before that there were other DoS attacks using udp and/or syn floods, and some of them likely involved several computers (and possibly people) working in coordination. Those several computers were probably not compromised machines that had malware responding to a cnc server, so the squishiness has to do in part with how exactly one defines DDoS - some definitions include a botnet requirement, others just need multiple computers working in coordination. It's claimed that Kevin Mitnick was targeting his prosecutor with syn floods in 1994 (over 30 years ago), but its not fully verified and the details are unknown from my research... likely though >1 computers were involved in that flood if it happened. In the early 90s there were all sorts of fun and games where people would knock over IRC servers by triggering bugs/behaviors in a lot of connected clients. It's primitive but it seems to have a huge number of elements of DDoS. Similar for attacks on various telecomms infrastructure as the soviet union/eastern bloc fell apart in that time period. Trying to put a hard "29 years ago" line in the sand is difficult to do... techniques evolve from previous ones and there are shared elements that make the line necessarily fuzzy. So yeah... theres no reason to quibble about "three decades" since theres 35+ years of history around "things that look like DDoS attacks but don't fit a strict definition that requires botnets"

jakub_g 1y ago

> QOTD DDoS attack > How it works: Abuses the Quote of the Day (QOTD) Protocol, which listens on UDP port 17 and responds with a short quote or message. Does any reasonable operating system those days support this protocol? Sounds like "IP over Avian Carriers" to me.

unilynx 1y ago
They're not an April fool's joke. A 90's linux might have these services enabled by default. I assume they were built to make network debugging slightly less boring
- skeezyboy 1y ago
  [dead]
toast0 1y ago
Is it part of Microsoft Services for Unix? That seemed to be the primary source of chargen reflectors when I was getting hit by that; and it feels like a similar thing.
NoboruWataya 1y ago
Huh, this sounds kind of cool, I like the idea of there being a few QOTD servers dotted around the internet. Shame that the first I'm heading about it is it being abused to launch a DDOS.
- msgodel 1y ago
  You can always ssh to random hosts and read the netbanners. Of course nearly all of them are a long paragraph or two of legal jargon that more or less boils down to "fuck off."
  - Retr0id 1y ago
    SSH banners come over TCP, requiring the 3-way handshake first, meaning you can't use it for traffic reflection (beyond the SYN-ACK itself).

wrs 1y ago

What was the goal of an attack lasting only 45 seconds?

dylan604 1y ago
Maybe someone was interested in buying the services, and the creator need to prove the capabilities. I'm sure there's other reasons too.
dc396 1y ago
A few options: - testing in preparation for a future attack - proof of capability ("Nice network you have there. It'd be a shame if something happened to it") - misfire ('What happens when I push this button that says "don't push"?')
mxuribe 1y ago
I was thinking reconn...but the other reasons cited by others here seem totally viable too.

NetOpWibby 1y ago

Cloudflare is the One Punch Man of the internet

johnklos 1y ago
Cloudflare protects scammers and want to recentralize the Internet around a for-profit company based in the Untied States. One-Punch Man is a reluctant mentor, is often broke, loves ramen and cares about others. They are not the same.

pariainterpares 1y ago

Any proof that this happened except cloudflare claiming it did? Just wondering whether these kind of attacks are seen by other orgs.

slt2021 1y ago

L4 level ddos is useless and is easily protected by Cloudflare. App level DOS use Cloudflare evasion techniques and directly DOS the destination server, while keeping itself undetected by Cloudflare's systems. Do not assume that Cloudflare will protect you from all attacks, if your app is dogshit python/js/php then even cloudflare wont protect you from L7 DDOS

deleted 1y ago

[deleted]

ripberge 1y ago

Huh, I got attacked from 170 countries last year (HTTP) and Cloudflare's autonomous detection (machine learning powered) rules did almost nothing. It was millions of the same requests over and over and the only thing that we could do to stop it was manually put in rules to block routes. Not only that, some of the attacking traffic came from within Cloudflare workers or it was at least going through their WARP client (those details are now fuzzy). Was a pretty miserable failure to perform on their part.

reassess_blind 1y ago
How many requests per second?
pacalleri 1y ago
Similar experience last week. But tbh I'm using the free plan so I wasn't expecting too much from them. What it worked was to use nginx rate limiter aggressively, parse logs and deny top ips with nginx. Because all traffic comes through CF I wasn't able to use iptables for blocking
- reassess_blind 1y ago
  Cloudflare’s has a free rate limit feature, btw. Not as configurable as nginx but it’s nice to not have the requests touch your server at all.
- hombre_fatal 1y ago
  If you can thwart it with your own nginx, then it can’t be much of an attack. Cloudflare is one of your only hopes against a volumetric attack especially when paying $0.

knowitnone 1y ago

Should Cloudflare release the IPs and try to get those devices removed from the internet?

_alternator_ 1y ago
That would just be a target list for hackers. Most of the devices that take part are going to be in homes or SMBs with old firmware that’s subject to known vulnerabilities. They will give the list to AS operators who request the offending IPs (presumably restricted to the AS ranges) but dropping it out on the public internet just invites trouble.
mschuster91 1y ago
They could but it's whack-a-mole and most ISPs just route abuse reports straight to /dev/null. IMHO, ISPs caught in that act should get yanked off the internet.
miyuru 1y ago
they do for ISPs who wants to do it. this is referred in the "Free botnet threat feed" of the article.
AtNightWeCode 1y ago
Not sure about CF but a lot of corps report to https://www.abuseipdb.com https://www.abuseipdb.com. So it is not hard to get the IPs of attackers.

dangoodmanUT 1y ago

It almost feels like writing about this is exactly what the attacker wants: Free validation and advertisement for exactly what their botnet can do

creatonez 1y ago
Is this a sign that A: Cloudflare is feeding the trolls because they think that they are invincible. Or: These post-mortems don't establish any proof that the attack was successful, especially if they are covering DDoSes that were barely even noticed by the public until CF publishes a blog post 1 month later -- so it's actually embarrassing for them and hurts their ability to market botnets for rent, at least once they no longer have the literal world record. B: Cloudflare is feeding the trolls for free testing scenarios to improve the mitigation C: The trolls don't really care if you feed them, large DDoS is something that's happening all the time anyways
- kevindamm 1y ago
  D: all of the above
- motorest 1y ago
  > Is this a sign that Isn't the obvious point that this is Cloudflare advertising their anti-DDoS services?
v5v3 1y ago
But now the ip's of their botnet are known, the bot net is weakened. Also it makes no sense - why throw 7.3tbps at a server, when half of that or less would have the same effect and not exposed your botnet.

m463 1y ago

meanwhile, cloudflare has been blocking my reading of websites more and more.

yamapikarya 1y ago

i just depends on waf, as long as the ddos attack does not reach my server. is that ok?

AngryData 1y ago

Sort of neat, but also feels like this post is 95% marketing and PR because its just a cherry picked example of success.

codedokode 1y ago

The main problem is that there is no "STOP" protocol, where you can send a packet indicating that you do not want to receive traffic from given AS or IP. Or at least that you are not going to pay for it. I think we need to support blocking at least on /24 prefix level.

kevmo314 1y ago

This article taught be about the QOTD protocol: https://datatracker.ietf.org/doc/html/rfc865 https://datatracker.ietf.org/doc/html/rfc865 Cool artifact of the internet!

jkingsman 1y ago
I run it inside my private network because it's cute. I wrote a toy C utility and made it Docker-friendly so I could just toss it at proxmox. https://github.com/jkingsman/RFC865-QotD-Server-for-Docker https://github.com/jkingsman/RFC865-QotD-Server-for-Docker

victorstanciu 1y ago

@tete called it: https://news.ycombinator.com/item?id=44262324 https://news.ycombinator.com/item?id=44262324

haxton 1y ago
Unrelated. Has nothing to do with the gcp outage that was related to.
esseph 1y ago
No, this is old.
- esseph 1y ago
  Oops - My mistake, this is not the attack that got stopped earlier this year that broke the previous record.

lordnacho 1y ago

Possibly the only kind of advertising that I actually like. Informative, engaging, no overselling.

candiddevmike 1y ago

What does this botnet do when it's not performing a 7.3 Tbps DDoS? Yea it's probably regular folks computers, but what "wakes up" the botnet to attack? What makes an attack target worthwhile? Presumably something this large would be on someone's radar...

jamessinghal 1y ago
The Command-and-Control part of the botnet would be whatever component they build to instruct it to attack; often using some dummy website they register and have the compromised clients poll for changes with instructions. I think an increasing amount of them are state actors or groups offering the botnet as a service.
- esseph 1y ago
  also add in DNS fastflux https://www.cisa.gov/news-events/cybersecurity-advisories/aa25-093a https://www.cisa.gov/news-events/cybersecurity-advisories/aa... https://www.cloudflare.com/learning/dns/dns-fast-flux/ https://www.cloudflare.com/learning/dns/dns-fast-flux/
toast0 1y ago
I mean... 7 Tbps sounds like a lot, but 1Gbps symetric connections are common in many areas. 7,000 botnet nodes with good connectivity can deliver that. The article says the attack traffic came from 122,145 source IPs, but I would expect at least some traffic to be spoofed.
rasz 1y ago
>What does this botnet do when it's not performing a 7.3 Tbps DDoS? Living their best "Im a retail Asus router/iot from Amazon" life.

password4321 1y ago

← Inserting standard complaint about Cloudflare protecting the sites selling these DDoS attacks here (at best: a conflict of interest selling the cure while protecting the disease).

jonathanlydall 1y ago
How does CloudFlare protect the disease? Also worth noting that the article specifically mentions how owners of ASNs can subscribe to CloudFlare at no charge to get notified when devices on their network are participating in attacks like this.
- Spivak 1y ago
  I think by treating the symptom they end up making it so that people don't actually do anything of substance in response to these absolutely massive attacks. Just put your site behind Cloudflare, obviously. Problems solved. Why do we need to do anything else?
- password4321 1y ago
  > Cloudflare protect[s] the sites selling these DDoS attacks Not a new problem per https://krebsonsecurity.com/2014/02/the-new-normal-200-400-gbps-ddos-attacks/ https://krebsonsecurity.com/2014/02/the-new-normal-200-400-g... a funny thing happens when you decide to operate a DDoS-for-hire Web service: Your service becomes the target of attacks from competing DDoS-for-hire services. Hence, a majority of these services have chosen to avail themselves of Cloudflare’s free content distribution service

sparrish 1y ago

Anybody know who the "Cloudflare customer, a hosting provider" was and what IP they were targeting and why? I'm curious why someone would go to such great lengths to try to take down a service.

porkloin 1y ago
I don't know who the provider is, but the attack was almost certainly not targeting the provider, but a site hosted on their platform. Many hosting companies upsell their customers into stuff like providing Cloudflare DDoS prevention. The target site was probably something political or controversial. I work at a hosting provider and we deal with this type of thing constantly.
- overfeed 1y ago
  > The target site was probably something political or controversial. Since this is Cloudflare, my headcanon is that it was a rival DDOS service, after a wild flamewar on some .ru hacker forum.
toast0 1y ago
The article says it was a 45 second attack. I used to run a high profile website which used to get a lot of 90 second attacks. Best I could figure was some of the ddos as a services would give a short attack as a free sample, and people picked us cause we were high profile. Thankfully, these would almost always attack our website rather than our service, and availability for our website didn't really matter. Most of the attacks weren't a big deal, and they'd get bored and move on to something else. The ones that did take a web server down were kind of nice... I could use those to tune both the webservers and the servers doing real work.