7 ms·
25-GPU cluster cracks every standard Windows password in less than 6 hours
- patrickgzill 14y agoIf this is done with commodity hardware, now, what were the NSA's capabilities even 5 years ago?
- SenorWilson 14y agoI'm sure they were able to crack the encryption method before Microsoft started using it.
- bradleyland 14y agoPut your tin foil hats away. This doesn't "crack" NTLM, it brute forces at a very high rate. The NSA has more money to spend, but are similarly limited by the hardware available at any given point.
- patrickgzill 14y agoThe NSA has access to their own chip fabrication facilities. I do not know if they own their own plant, or just have secure fab space at some other company's plant. So they could have easily fabbed something like this, or a tuned architecture specifically designed for the purpose.
- plaguuuuuu 14y agoIt's very probable that they have and if so, it's almost certain that it would involve specialized hardware implementations (ASIC, FPGA, whatever) rather than commodity graphics hardware which is burdened with expensive and useless stuff like onboard memory and would be power inefficient considering that the entire purpose of NSA in the first place is to provide SIGINT and encrypt or decrypt signals, it's almost a given that they're trying to the best of their ability to crack stuff.
- raverbashing 14y agoNot sure Money buys more commodity hardware faster than the time/money used to develop a chip It's not hard to make tens, or maybe even hundreds of GPUs beat a specialized chip except for very specific things And even for something specialized it's probably easier to use an FPGA
- mrb 14y agoNSA does not own a foundry anymore. Modern top-of-the-line foundries cost too much, even for the NSA. Instead, they participate in a program to partner with domestic companies to manufacture their chips: http://trustedfoundryprogram.org/ http://trustedfoundryprogram.org/
- apawloski 14y agoFor comparison, a couple weeks ago Oak Ridge National Laboratory's Titan computer topped the Top500 list for fastest supercomputer in the world (although that title is a bit misleading). Here's the specs on Titan: 18,688 AMD Opteron 6274 16-core CPUs 18,688 Nvidia Tesla K20 GPUs 17.59 petaflops Titan displaced Sequoia (at Lawrence Livermore National Laboratory) from the top spot on Top500. Interestingly enough, Sequoia uses a very different architecture, based on 16-core PowerPC A2 nodes rather than GPUs. Sequoia also has about 1.6PB of memory, while Titan "only" has 1PB. Both computers have reasonably different use cases. GPUs are great for embarrassingly parallel, non-memory intensive tasks like brute forcing passwords. But all of the rumors about the NSA's massive data analysis needs suggests that they may need a cluster that resembles Sequoia (with fewer cores, but larger caches and available memory) more than Titan.
- muyuu 14y agoI wouldn't call a big cluster of commodity hardware simply commodity hardware because then many of the top supercomputers of the world are commodity hardware. The combination is exotic enough to be considered non-commodity hardware.
- recoiledsnake 14y agoEvery standard Windows password less than 8 chars only?
- apawloski 14y agoI know for practical purposes this doesn't seem like that big of a deal, but you have to understand that 8 chars of mixed case, numbers, and symbols is still a gigantic key space. That this can be done so quickly on commodity hardware is pretty impressive.
- hayksaakian 14y agoIndividual char variance is less significant compared to additional chars. Look at the xkcd password entropy comic
- apawloski 14y agoI'm not sure what you're disagreeing with here. Are you saying that 9-characters translates to a significantly larger than key space than 8 characters? Well, yeah -- of course. My point is that this is still a noteworthy feat.
- Caerus 14y agoFrom what I remember of the comic, the point was not the length of the password. The entropy was calculated based on 4 possible words. Assuming ~2000 common English words, the number of possible passwords in that format is 2000^4 ~= 2^44. If the calculation is based on a completely random string of letters it is far stronger at 26^30 ~= 2^141 but it's safe to assume people aren't going to memorize a 30 character random password. It's worth noting that the fairly common 8 character upper/lower case, numbers, and symbols they cracked in 6 hours is more secure than "correcthorsebatterystaple" at 72^8 ~= 2^49.
- hayksaakian 14y agoWhy would that be true? Wouldn't you have to know in advance that the longer password was only lower case letters?
- spqr 14y agoStupid title. This guy could double his cluster and never hope to crack a single 9 digit password let alone anything longer than that.
- cynwoody 14y agoImpressive as the numbers are, it's worth remembering that this is an "offline crack", going against a stolen list of encrypted passwords. If they can steal your database of encrypted passwords, you've got a problem no matter how strong the passwords are. How many guesses per second do you get in a typical online crack? E.g., a script kiddie trying to guess your cloud server's SSH password?
- ramidarigaz 14y agoOn my webserver, you get 3 chances and then a 24 hour ip ban. I think that comes out to 0.00003 passwords per second :) The particularly persistent IPs get a special iptables rule.
- obilgic 14y agoCould you share the details of the implementation please?
- ramidarigaz 14y agoNot much implementation actually. Fail2ban does all the hard work, and then if I get too many emails reporting the same IP I go in and manually permaban the offending IP (doesn't happen often).
- deleted 14y ago[deleted]
- cgag 14y agoI suppose it's a bit different from a user facing login, but does anyone know why these limits tend to be set so low? I've locked myself out of plenty of things, and so have plenty of people I know. It seems like setting the limit to 20 would be just as effective in blocking brute force attacks without being user unfriendly. Is it that with user facing services the common user/passwords are so common it's reasonable to just try just the top x most common passwords?
- 14y ago
- rayval 14y agoEdited title for length, because original title got truncated in a confusing fashion. Original title: "25-GPU cluster cracks every standard Windows password in <6 hours"
- rayval 14y agoLooks like that got fixed by sysop gods. Thanks!
- namank 14y agoHow bout SSL?
- iamchrisle 14y agoNice. But can it run Crysis?
- rtkwe 14y agoYes. Physically, it's running *nix though so you'd have to get windows to not freak out with all that power.
- jwilliams 14y agoThis was discussed 3-4 days ago: http://news.ycombinator.com/item?id=4875206 http://news.ycombinator.com/item?id=4875206 Upshot - it's impressive, but NTLM already known as an vulnerable target.
- madao 14y agoI remember back when I was doing a network engineering course the guys could crack a windows password in minutes offline, simple matter of grabbing the database from the machine. I think once you have the machine offline unless you encrypt the data your pretty screwed regardless..
- Blara 14y agoWhen was this? I know older windows versions stored passwords in plain text... I can't remember when they switched to hashed passwords but I think it was around XP or Vista
- muyuu 14y agoWindows never stored system passwords in plain text. It did use the LM hash function to store passwords, which was rather weak, making rainbow table attacks easy. http://en.wikipedia.org/wiki/LM_hash http://en.wikipedia.org/wiki/LM_hash For backwards compatible this hash function was commonly in use up to Windows 7 (it was disabled by default in Vista though). There are decent workarounds since NT. NTLMv1 is also rather easy to crack. NTLMv2 is better but took a long time to be in wide use. Kerberos is strong too and can be used Long story short, Windows OS prior to Vista maintain weaker hash support for backwards compatibility by default (although you can work around it since NT 4, almost nobody did this). Windows Vista still has support for them if you want to turn it on, but by default it's off. From Windows 7 there is no support for weak system hashes. For Active Directories, MIT's Kerberos (used typically in Unix networked environments since the 80s) replaced NTLM from Windows 2000 on.
- jiggy2011 14y agoYou might be thinking of a very old version of Windows, like 3.1 vintage. 3.1 didn't really have passwords to access the system, it did however have screensaver passwords which were either plain text or a very weak hash. They could also be disabled by simply deleting the line for a .ini file which was bad considering it didn't have the concept of users who could only access certain files.
- rjempson 14y agoI'm not sure there is much significance to this article. It points out "The technique doesn't apply to online attacks, because, among other reasons, most websites limit the number of guesses that can be made for a given account." Same applies to Windows.
- rjempson 14y agoThinking about it some more. Is the only practical exploit of this the case where a rogue sysadmin wants to figure out user passwords (without resetting the password and therefore alerting the user)?
- ramblerman 14y agoI think what they're referring to is having access to the physicial harddisk. In linux terms it would equate to having a copy of the /etc/passwd file. For example the FBI seizes someones computer. This would allow them to brute force without said restriction. So yes, from an online, or standard entry viewpoint this is a moot point. Also a properly encrypted hard drive using something like truecrypt is still pretty impenetrable regardless.
- halviti 14y agoI've grabbed the SAM file from remote IIS servers in my younger years and cracked the passwords locally. Buffer overflow the web service, bind a command shell to a port running as the system account (by having the system execute shellcode used in the buffer overflow), netcat to your open port, ftp the SAM (located in the repair directory) to somewhere you can retrieve it, download the file, delete all of the logs, crack the file. Hard drive encryption would have done nothing to prevent this.
- ygra 14y agoI doubt law enforcement would go that route if they seized your stuff.
- deleted 14y ago
- peteretep 14y agoLess good against non-NTLM passwords ... from my comment last time: Taking SHA-1 (which YOU MUST NOT USE for password hashing blah), it only manages 63 billion a second. To try all the passwords for that in the alphanumeric space: - 10 chars: 35 weeks - 11 chars: 44 years - 12 chars: 2,800 years - 16 chars: 11 times the age of the sun 10 chars for bcrypt: 600,000 years... http://www.wolframalpha.com/input/?i=%2865**16+%2F+63+billion%29+seconds http://www.wolframalpha.com/input/?i=%2865**16+%2F+63+billio...
- muyuu 14y agohttp://www.imdb.com/title/tt0109686/quotes?qt=qt0383410 http://www.imdb.com/title/tt0109686/quotes?qt=qt0383410 Lloyd: What are my chances? Mary: Not good. Lloyd: You mean, not good like one out of a hundred? Mary: I'd say more like one out of a million. [pause] Lloyd: So you're telling me there's a chance... YEAH!
- joshmaker 14y ago- 8 chars: 84 minutes - 6 chars: 1.2 seconds All of which demonstrates the importance of requiring longer passwords. Also, keep in mind that these are maximum times required to crack a password and not the average times.
- mikeash 14y agoThe average time to crack will just be half of the maximum, so it's not a big difference (compared to order of magnitude errors, anyway). Still good to point out, though.
- nodata 14y agoSure? Wouldn't you optimise the attack to try words or wordlike c0mb1n4t1ons first?
- stephengillie 14y agoThat's a good idea if the password was human-generated. With computer-generated random passwords, like gH8r;2CpyyK!a, you might want to optimize differently.
- ChrisNorstrom 14y agoGuess what? Back in 2009, I started using a method to remember long passwords with a huge # of letters, numbers, & special characters. Gw?Bi2009Isuamtrlpwah#ol,n,&sc. (31 characters) Create memorable sentences and create a password using the first letter of each word & all the numbers and punctuation. After entering it 10 or so times you'll get used to it pretty quickly.
- phpnode 14y agoor you can literally write the whole sentence, which is even more secure and you don't have to remember any special rules, just the sentence itself. Of course it's more typing: Guess what? Back in 2009 I saw a uniquely attired man traipsing round local places with a high number of legs, necks and shirt collars. 136 characters or 14 Gigayears to crack. Wow today I learnt that there's such a thing as a Gigayear.
- sunraa 14y agoI just went through the process of changing passwords to sentences. You'd be surprised at how many sites do not allow sentences.
- ccheney 14y agoWhat irks me is when they reject special characters like ?!#$@", etc.
- SageRaven 14y agoI use a password manager, and I have a unique password per site. I generally try to use an MD5 hash resulting from a "ps waux | md5" at the time of registration. I've encountered sites that rejected this due to lack of upper characters (oracle.com, which then allowed me to use "Abc123"), having no special characters, being too long (often forcing me to down-size to 16 or 8 chars). The worst are sites that silently truncate long passwords (I'm guessing due to code errors), so your password is invalid the second you register and must immediately proceed with a password reset. Big sites are generally good about allowing long/strong passwords. Many mom-n-pop sites are often hit-or-miss.
- 16s 14y agoNTLM hashes are stored in Active Directory servers as one round of unsalted MD4. It's plain MD4. Not many people know this and I only point it out as it's important to understand that when talking about how many cracks per second they are getting.
- jiggy2011 14y agoSo , why don't modern versions of Windows just use Bcrypt or similar for passwords?
- dj_sa 14y agoMy password is 24 chracters long, and fully random. I don't memorise it. I use Aladdin to type it for me. http://igg.me/aladdin-key http://igg.me/aladdin-key Aladdin is trying to improve the current situation of people using simple or identical passwords everywhere by removing the need to memorise passwords. Aladdin works with Windows, Mac, Linux as well as Android and iPad. Aladdin is a USB key(board). No software needed.
- mikejordan 14y agoI know a Windows password recovery tool called SmartKey Windows Password Recovery. It is great. From http://www.recoverlostpassword.com http://www.recoverlostpassword.com