AWS

Cheap And Easy Cloud Cracking On The Way

Jeremy Brown

Jeremy Brown

— 3 min read

Ama­zon recently announced a new instance type for their EC2 cloud ser­vice that they call the Clus­ter GPU which has an impres­sive spec:

22 GB of mem­ory
33.5 EC2 Com­pute Units (2 x Intel Xeon X5570, quad-core Nehalem archi­tec­ture)
2 x NVIDIA Tesla “Fer­miâ€� M2050 GPUs
1690 GB of instance stor­age
64-bit plat­form
I/O Per­for­mance: Very High (10 Giga­bit Ethernet)

The really inter­est­ing part that has got a lot of peo­ple inter­ested is the fact that it has two high-powered graph­ics cards which can be used to do mas­sively pow­er­ful par­al­lel com­put­ing. Now there are many poten­tial appli­ca­tions for these GPUs — image and video pro­cess­ing, com­pu­ta­tional biol­ogy and chem­istry, fluid dynam­ics sim­u­la­tion, CT image recon­struc­tion, seis­mic analy­sis, ray trac­ing and so on. But what really inter­ests me is the pos­si­bil­ity of using these GPU instances for pass­word cracking.

It’s now well-known that using a GPU to crack pass­words can reduce the time required from some­thing like 2 months to 3 days, but what hap­pens when you throw one of these new Ama­zon instances at the prob­lem? And what if it’s not just one instance but a clus­ter of them that is used to do the mas­sively par­al­lel com­pu­ta­tion? The sheer com­put­ing power that even a small clus­ter of these machines has avail­able would make short work of crack­ing all sorts of pass­words. Some that come to mind are:

  • Sys­tem Pass­word files which use the MD4, MD5, NTLM or SHA1 algorithms.
  • WPA-PSK or WPA2-PSK net­work pass­words (WEP is already triv­ial to crack).
  • Pass­word pro­tected RAR or ZIP files.
  • Pass­word pro­tected Microsoft Office or Open Office files.
  • Pass­word pro­tected PDFs.
  • Encrypted disks

Some peo­ple have already tested these GPU instances to crack pass­word hashes and Pyrit has been tested on it (could be used to crack WPA/WPA2). The per­for­mance of a sin­gle instance is impres­sive, the cost is equally impres­sive($2.10 for an hour). Just a few years ago this kind of com­put­ing power was only avail­able to organ­i­sa­tions that had a large amount of resources such as gov­ern­ments, large cor­po­ra­tions and a few uni­ver­si­ties and research organ­i­sa­tions. Now any­one with a bit of tech­ni­cal knowl­edge and a credit card has access to it.

It’s only a mat­ter of time before some­one uses a clus­ter of these instances in anger to start crack­ing pass­words, in fact I’m sure some­one already is. How long will it be before some­one releases a com­mer­cial ser­vice based on this platform?

The only com­mer­cial ser­vice for pass­word crack­ing that I’ve found so far is WPA Cracker who claim to have a 400 CPU clus­ter, how­ever a ser­vice that uses a few EC2 GPU instances could blow away the per­for­mance of WPA Cracker. We could soon start to see pass­words being cracked in just a few min­utes with a large enough clus­ter. I wouldn’t be sur­prised if it wasn’t long before some­one sets up a ser­vice like this which inte­grates nicely into back­track or some other wi-fi sniff­ing soft­ware that grabs the required wi-fi pack­ets and uploads it to an EC2 clus­ter that cracks the pass­word in a few minutes.

All of this is a very strong argu­ment for using longer and more com­plex pass­words that are less vul­ner­a­ble to dic­tio­nary and brute force attacks, and one more rea­son not to assume that your wi-fi net­work is secure because you are using WPA or WPA2 instead of WEP.

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