Windows passwords easily guessed by 25-GPU server

Ever wondered how secure the password to your Windows workstation is? Well, as it turns out, it's pretty insecure when put up against a 25-GPU server cluster running a combination of Linux and freely available password-cracking software suites. Said server, powered by 25 AMD Radeon graphics cards, manages to brute force Windows passwords at a rate of 350 billion guesses-per-second, making short work of eight-character passwords.

This is one of five servers that eats passwords for breakfast

In around 5.5 hours the server cluster can try 6.6 quadrillion password combinations, enough to check every possible eight-character password including upper/lower-case letters, digits and symbols. Microsoft's NTLM cryptographic algorithm, which has been in use since Windows Server 2003, now seems remarkably weak and particularly insecure in some enterprise settings. With access to a hash of a workstation password, this machine will most likely be able to crack it in under a day.

Of course, this machine can only really guess passwords up to eight characters in a reasonable time, as adding just one extra character (to nine characters total) would require 500 hours to crack; 10 characters and you're looking at 5.4 years of cracking time. However, as many businesses stipulate eight characters as a minimum, there's a possibility that this machine will make (relatively-speaking) short work of it.

This 25-GPU machine is not limited to just cracking Windows passwords - it also has the power to guess at 44 other algorithms at a blistering pace. It attacks SHA1 at 63 billion guesses per second and MD5 at 180 billion guesses per second, although struggles against some super-tough encryption such as SHA512crypt (just 364,000 guesses per second).

What should you make of this information? Don't make your passwords anything less than nine characters long, and of course don't use a word or phrase that might appear in a dictionary.

Source: Ars Technica | Image via Ars Technica

Report a problem with article
Previous Story

Piracy issues shuts down NZBMatrix

Next Story

Next at Microsoft blog launches its own Windows 8 app

71 Comments

Commenting is disabled on this article.

My 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

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.

8 cards in the picture ?
I've never seen a motherboard where you can plug in 8 PCIe cards that's nuts !
I'd like to see a story on that hardware playing some games that are hard to run full spec.
and i wonder could they speed up the whole attack by using a *proper graphics card ?
ATI really ? come on lol
IF they wanna do it right they should have used nVidia GPU's and the OC'd those mutha's !!!

I am Not PCyr said,
8 cards in the picture ?
I've never seen a motherboard where you can plug in 8 PCIe cards that's nuts !
I'd like to see a story on that hardware playing some games that are hard to run full spec.
and i wonder could they speed up the whole attack by using a *proper graphics card ?
ATI really ? come on lol
IF they wanna do it right they should have used nVidia GPU's and the OC'd those mutha's !!!

I`m glad at least 2 other people saw it and it wan`t just me thinking iv`e gone daft. Apparenrly VCL (Virtual Open Cluster) can support up to 128 AMD GPU`s........that`s numberwang

I'm a bit curious, the article says it's a 25-GPU cluster. The picture shows an server with 8 GPU cards. Now where does that odd GPU come from? The internal one? Probably not in a server box. The image text says "It's one of five servers that make up a high-performance password-cracking cluster." which means there are servers with less GPU cards, or else it would have been a 40-GPU cluster (at least).

I think it would have been wise to include the little detail of local machine access needed, and as we all know security of any system fails when the physical security fails. The only instance this matters as far as I can see if for bitlocker encrypted drives on laptops left somewhere or stolen (desktops as well but not so much), as people would be using bitlocker for this specific purpose.

So if using bitlocker to protect data, make your password longer. Simples.

BS article is BS.
"NTLM hashes seem weak. [...] adding just one extra character would require 500 hours to crack".

In other news SETI is using millions of computers to hack to crack Russian passwords.. Is SETI really processing aliens data ? #consipracy

Boot with Offline NT Password & Registry Editor, select clear password.

Windows passwords are a joke, though I realize that's not really what this article is about.

TRC said,
Boot with Offline NT Password & Registry Editor, select clear password.

Windows passwords are a joke, though I realize that's not really what this article is about.

Not that any system has secure passwords. Even in Linux, if you have access to the machine, it's toast (Linux keeps passwords as hashes in a text file, all you have to do is replace the hash)

Blah Blah Blah

This has virtually NOTHING to do with Windows, and presents a straw man argument that is not obtainable.

Doing a brute force attack on the hash file, first requires getting the SAM/Hash file assuming it is even stored on a local machine, then decrypting the 128bit RC4 used, and then attacking the NTLM passwords.

Just breaking the 128bit encryption will take about 4-5 billion years even on a supercomputer before the brute force attack can even be started.


This has nothing to do with Windows security or NTLM, it is just a demonstration of raw computing power using a GP-GPU array.


They could have picked any security system, and being a Linux project, didn't want to pick on one of their own, which ironically is easier to break.

thenetavenger said,
Blah Blah Blah

This has virtually NOTHING to do with Windows, and presents a straw man argument that is not obtainable.

Doing a brute force attack on the hash file, first requires getting the SAM/Hash file assuming it is even stored on a local machine, then decrypting the 128bit RC4 used, and then attacking the NTLM passwords.

Just breaking the 128bit encryption will take about 4-5 billion years even on a supercomputer before the brute force attack can even be started.


This has nothing to do with Windows security or NTLM, it is just a demonstration of raw computing power using a GP-GPU array.


They could have picked any security system, and being a Linux project, didn't want to pick on one of their own, which ironically is easier to break.

they did and that would be why they said it supports 44 algo's such as MD5
the story was making a point which INLCUDED windows passwords.

and billions of years ? sorry no..
because pc technology gets better the speed in which you would finish would get faster and faster as time went on.

and "on the hash file" ?
where is the hash file before I address that "fact" ?
in other words explain yourself.. where is the password stored ?

ArialBlue said,
While you be an idiot and waste time and money on your GPU server, I will simply take your HD.


And if the user has something important on it,it'll be locked with bit locker and you have stolen a paperweight.

Any enterprise running active directory would have a password policy that should block this from trying any more then 3 incorrect times in 10 minutes. That would stop this sort of brute force approach wouldn't it?

Rukus said,
Any enterprise running active directory would have a password policy that should block this from trying any more then 3 incorrect times in 10 minutes. That would stop this sort of brute force approach wouldn't it?

That has nothing to do with this. You can only run a bruteforce that these run if you have the hashed password (SAM file) from the system you're trying to crack. It will not work against a live system.

n_K said,

That has nothing to do with this. You can only run a bruteforce that these run if you have the hashed password (SAM file) from the system you're trying to crack. It will not work against a live system.

However, people are forgetting that gaining access to the SAM is not easy or information just laying around.

If even you use only a local workstation hashed SAM, it is 128bit RC4, which is going to take a few BILLION years to decrypt before even beginning to run the brute force attack on the NTLM passwords.

Most people don't have 4 or 5 billion years just to get access to the SAM.

thenetavenger said,

However, people are forgetting that gaining access to the SAM is not easy or information just laying around.

If even you use only a local workstation hashed SAM, it is 128bit RC4, which is going to take a few BILLION years to decrypt before even beginning to run the brute force attack on the NTLM passwords.

Most people don't have 4 or 5 billion years just to get access to the SAM.

am i missing something ?

http://reboot.pro/files/file/95-rawreg/

http://nunobrito1981.blogspot....uded-in-pwning-bootkit.html

surely you could get 6 of these and set it so 1 does 1-8 characters ....another does 10 characters the next two do 11 and 3 do 12 ... passwords cracked all you needs is lots of money ! >_> obviously you need alot more then what i said but just an idea more servers with a load sharer

SPEhosting said,
surely you could get 6 of these and set it so 1 does 1-8 characters ....another does 10 characters the next two do 11 and 3 do 12 ... passwords cracked all you needs is lots of money ! >_> obviously you need alot more then what i said but just an idea more servers with a load sharer

The increase in the number of possible passwords increases way more than linearly with length.

SPEhosting said,
surely you could get 6 of these and set it so 1 does 1-8 characters ....another does 10 characters the next two do 11 and 3 do 12 ... passwords cracked all you needs is lots of money ! >_> obviously you need alot more then what i said but just an idea more servers with a load sharer

not possible

the password has to be checked in its entire form. you can't split it into 2 pieces and have one machine do half and another do the other half. it would never work.

I am Not PCyr said,

not possible

the password has to be checked in its entire form. you can't split it into 2 pieces and have one machine do half and another do the other half. it would never work.


noo you looked at it wrong you can always tell a computer to start decoding from eeeeeeeeeee and another one to start at aaaaaaaaa and finish at eeeeeeedget the same password just have different start points

SPEhosting said,

noo you looked at it wrong you can always tell a computer to start decoding from eeeeeeeeeee and another one to start at aaaaaaaaa and finish at eeeeeeedget the same password just have different start points

you may be right i don't kow much about algo's and cracking them.. when i try and circumvent a protection scheme that uses them i just go around them lol
OR i don't bother.. the rainbow tables concept is as old as pc's them selves i would be willing to bet but i have never ever felt motivated to use them.

anyway i think it all depends on the code that checks a password etc
and that in this topic isn't stated and we were talking in general so i dunno lol
but if you take a hash like an MD5 hash such as stated in this story and you try and reverse / crack / break it etc I just can't wrap my head around how it would be possible to reverse it in parts (say 2 parts for example) because the target object is no good unless its in its full form.. like i don't see how you could pull the same info from a hash as you could from half of that same hash when half the data is missing. Don't forget we're talking 44 algo's in this story not 1 plain text password where a char can be checked etc.. Hash's were designed the way they are for a reason.

but like i said i may be totally wrong so just my thoughts on the comment you made..

Ryya said,
But does it run Crysis? Haha

properly not but i reckon it can play Pong with graphics maxed out

Edited by xSuRgEx, Dec 10 2012, 11:32am :

Well no ****, anyone can run it in under a day anyway using rainbow tables, so in other words this thing uses a hell of a lot more power and outputs a hell of a lot more heat than a normal PC but works on trying every password compared to a rainbow table up and they both take the same time but a PC wins having a power bill of a few quid for the 24 hours instead of something in the hundreds...

Why is this news ?

Matthew_Thepc said,
Is this talking about BitLocker, or just the default Windows user account password?

Regular Windows passwords is all I gathered from it.

Matthew_Thepc said,
Is this talking about BitLocker, or just the default Windows user account password?

Regular NTLM-type windows passwords.
Bitlocker doesn't need cracking because it's got an inbuilt recovery mechanism that law enforcement can use to access the data.

n_K said,

Bitlocker doesn't need cracking because it's got an inbuilt recovery mechanism that law enforcement can use to access the data.

interesting, do you have a source for this?

n_K said,

Regular NTLM-type windows passwords.
Bitlocker doesn't need cracking because it's got an inbuilt recovery mechanism that law enforcement can use to access the data.

Um, Bitlocker does NOT have a backdoor or recovery. You can use tools supplied by Microsoft like COFEE to take a snapshot of a logged in system, which works with any Volume/FS/RAM encryption technology and is not specific to Bitlocker.

If the machine is powered down, this access is lost and the user password must be obtained.

Guth said,
moral of the story?

long passwords!
I'm forever telling friends/family this.

Long passwords will save you from brute force attacks but I can tell you that they will not save you from password bypassing/removal save yourself the time and effort and just keep a short, easy to remember password for things!

Of course, this machine can only really guess passwords up to eight characters in a reasonable time, as adding just one extra character (to nine characters total) would require 500 hours to crack; 10 characters and you're looking at 5.4 years of cracking time. However, as many businesses stipulate eight characters as a minimum, there's a possibility that this machine will make (relatively-speaking) short work of it.

My local password is 23 units long. Good luck.

Relativity_17 said,

My local password is 23 units long. Good luck.

If you are referring to your windows password, I would boot off a cd and have that password wiped off your machine in about 30 seconds.

Relativity_17 said,

My local password is 23 units long. Good luck.

22 here, although it's mostly out of habit and being able to type it within 2 seconds.

Glassed Silver:mac

warwagon said,

If you are referring to your windows password, I would boot off a cd and have that password wiped off your machine in about 30 seconds.

haha exactly, I think if I booted off a USB 3.0 it would literally nuke it in about 10 seconds!

warwagon said,

If you are referring to your windows password, I would boot off a cd and have that password wiped off your machine in about 30 seconds.

First you have to obtain access to the computer security room, open the case, break the UEFI and reset it to gain boot privileges.

Next you have to break the NTFS encryption, which even with this GPU powered cracking machine will take you about 4 billion years.

Good luck...

thenetavenger said,

First you have to obtain access to the computer security room, open the case, break the UEFI and reset it to gain boot privileges.

Next you have to break the NTFS encryption, which even with this GPU powered cracking machine will take you about 4 billion years.

Good luck...

Or I can just put a .50 cal in your head and force you to tell me the password... in about 3 seconds lol

warwagon said,

If you are referring to your windows password, I would boot off a cd and have that password wiped off your machine in about 30 seconds.

ya i was thinking the same on this story.. why crack a password when you can find ways to circumvent the protection all together ?
brute force a windows password or use a boot cd with cracking tools to reset the password on an offline windows install ?
And thenetavenger
we ALL know.. sitting in front of a computer is different that not lol
that goes with out saying.. but the question would be is did the hardware in this story have to be directly plugged into the target pc ?
And sorry i don't see the part where they said this was an exclusive windows 8 attack

Relativity_17 said,

My local password is 23 units long. Good luck.

move your syskey file to a usb drive formatted in fat32 and set as a floppy disk in diskmanager. you will need it each time you boot your pc from a "cold boot" and then people who get access to your system wont be able to kon your system into accepting any password.

old concept and the results don't surprise me..
It's the hardware i find interesting !
I've never been able to plug in together 25 gfx cards lol

I am Not PCyr said,
old concept and the results don't surprise me..
It's the hardware i find interesting !
I've never been able to plug in together 25 gfx cards lol

Haha same here.
Actually it's awesome to see them hooked up so closely together...
Needs a hell of a good cooling system I guess.

GS:mac

Glassed Silver said,

Haha same here.
Actually it's awesome to see them hooked up so closely together...
Needs a hell of a good cooling system I guess.

GS:mac

cant wait for the day when Intel launch a cpu thats as fast as all those gfx chips combined into 1 LGA chip. lol

So my main 15 character alpha-numeric, upper/lower case, symbol based password is still safe then?

Be interesting to see how long it would take them, lol.

RazorEye said,
So my main 15 character alpha-numeric, upper/lower case, symbol based password is still safe then?

Be interesting to see how long it would take them, lol.

It could be 5 million digits, if a person has physical access, it takes one boot to remove.

RazorEye said,
So my main 15 character alpha-numeric, upper/lower case, symbol based password is still safe then?

Be interesting to see how long it would take them, lol.


nah... the real question is: but can it run crysis?

Angel Blue01 said,
Oh dear, I know a lot of users who have 2-3 character passwords

How about 10x GPU added to this series of 25 ?

Now days Super Computers made with consumer PC hardware is pretty cheap and one can easily take that No. 25 to No. 250.

Only thing i guess is difficult is the software platform which puts the cluster together

Do we really need a strong windows password? A 3 character password is enough to keep the village idiot off your machine.

Anyone else with physical access to / possession of your machine that knows their ass from a hole in the ground would just boot off a cd and nuke your password from orbitb.

If you really care, truecrypt with whole drive encryption and a strong password is where it's at.

Edited by warwagon, Dec 10 2012, 2:48am :

warwagon said,
Do we really need a strong windows password? A 3 character password is enough to keep the village idiot off your machine.

Anyone else with physical access to / possession of your machine that knows their ass from a hole in the ground would just boot off a cd and nuke your password from orbitb.

If you really care, truecrypt whole drive encryption with a strong password is where it's at.


This.

I don't think there's any reasonable IT person who thinks a "good" Windows password is a sensible means of protecting data.

GS:mac

warwagon said,
Do we really need a strong windows password? A 3 character password is enough to keep the village idiot off your machine.

Anyone else with physical access to / possession of your machine that knows their ass from a hole in the ground would just boot off a cd and nuke your password from orbitb.

If you really care, truecrypt with whole drive encryption and a strong password is where it's at.


hello is bitlocker safe enought for my machine? or truecrypt is better? I think read somewhere that truecrypt slows down hevavy your SSD and reduce its lifetime and bitlocker is faster and more efficient in SSD... only 10% performace hit vs 50% on truecrypt!!?

WinRT said,

hello is bitlocker safe enought for my machine? or truecrypt is better? I think read somewhere that truecrypt slows down hevavy your SSD and reduce its lifetime and bitlocker is faster and more efficient in SSD... only 10% performace hit vs 50% on truecrypt!!?


They're equally safe, but technically due to better integration, bit locker is probably better/more secure.

HawkMan said,


They're equally safe, but technically due to better integration, bit locker is probably better/more secure.

But if you encrypt a portable harddrive or usb stick, truecrypt may be better if you move around and use a few machines. It also has hidden volumes.

In other words, if you distribute your bruteforce algorithm workload over countless amount of cores, you get good results.

Why countless? Because a high end GPU has a lot of very simple cores / processing units.

The Windows password part is just click-bait it seems.

Coolicer said,
The Windows password part is just click-bait it seems.

Nope, actually this machine cracks Windows passwords the fastest of all the algorithms it's capable of, especially LM encrypted ones

Scorpus said,

Nope, actually this machine cracks Windows passwords the fastest of all the algorithms it's capable of, especially LM encrypted ones

Wrong, I've worked in cryptography for many years. NTLM is actually a relatively difficult algorithm to break but many researchers diverted their attention to it and developed short cuts for breaking it, the most common being rainbow tables. Rainbow tables fall apart at about 10 characters long which means if you were securing a PC that had some serious data on it you have longer passwords.

For the record, obtaining an NTLM hash isn't very easy, especially in Windows 8. The only real way is to have physical access to the computer (there are software based solutions but almost always detected) and if you have that then there are a lot simpler ways of gaining access to the computer than brute forcing the password. Windows passwords are for protecting Windows not your computer I advise power on passwords coupled with an HDD password or HDD encryption with truecrypt,

So yeah the Windows part was really click bait, these computers can crack any kind of algorithm as you said and I can assure you NTLM is not the easiest ever tried cracking plain text?

ingramator said,
...

To be fair, he said "fastest", not "easiest" and he didn't say it was the easiest ever, he said this machine can crack Windows passwords the fastest out of all the algorithms it can crack (out of the 44).

Whether that's true or not I don't know, but at least read his comment before replying.