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Amazon EC2 Enables Cheap Brute-Force Attacks
snydeq writes "German white-hat hacker Thomas Roth claims he can crack WPA-PSK-protected networks in six minutes using Amazon EC2 compute power — an attack that would cost him $1.68. The key? Amazon's new cluster GPU instances. 'GPUs are (depending on the algorithm and the implementation) some hundred times faster compared to standard quad-core CPUs when it comes to brute forcing SHA-1 and MD,' Roth explained. GPU-assisted servers were previously available only in supercomputers and not to the public at large, according to Roth; that's changed with EC2. Among the questions Roth's research raises is, what role should Amazon and other public-cloud service providers play in preventing customers from using their services to commit crimes?"
"what role should Amazon and other public-cloud service providers play in preventing customers from using their services to commit crimes?"
The same role that Ford Motor Company is responsible to fill in preventing the use of it's vehicles as Getaway cars from scenes of crimes.
There's a spot in User Info for World of Warcraft account names? Really?
Amazon provide infrastructure services. They need not, should not, must not know or seek to know how these services are used.
Oh wait, Wikileaks...
They who would give up an essential liberty for temporary security, deserve neither liberty or security - Ben Franklin
They should not take any steps in this direction. We should have learned that. it. just. don't. work. Brute-forcing a hash is not illegal anyway. If the customer of amazon decides to misuse the result, than this is not the responsibility of Amazon. Many services and tools can be abused for crime.
what role should Amazon and other public-cloud service providers play in preventing customers from using their services to commit crimes?"
No role whatsoever; let law enforcement agencies handle criminal investigations.
Palm trees and 8
Among the questions Roth's research raises is, what role should Amazon and other public-cloud service providers play in preventing customers from using their services to commit crimes?"
None whatsoever. Amazon and other service providers are retailers. They are not a police force. If a crime is being committed, let the designated authorities (i.e. cops) investigate it, police it, and arrest the criminal. No business should ever be involved in policing anything. That's a role specially held for the executive branch of governments.
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Probably because grandfathers tend not to be bitches.
It's actually 20 random characters that are recommended for use as cryptographic keys. The reason for this is that 20 random keys from the US keyboard has the same number of possible combinations as 128 random bits. If you use anything less than 20 random characters, even if you use a 128-bit encryption algorithm, you won't have 128-bit encryption. The same is true if you use 20 non-random characters. A brute-force attack would try passwords with words or phrases before going for the really random stuff, so you again don't have 128bit encryption.
Also fun to realize: for every character less than 20, you lose 100x your security. A 19-character password could be cracked in just 1% of the time of a 20-character password. A 10-character password would take .000000000000000001% of the time.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
I would expect Amazon to cooperate with the law enforcement should they discover that their service was abused to commit a crime. But why should they required to "avoid" it? And most of all, how? The only way to really keep people from using that service for criminal means would be to explicitly disallow certain uses and then monitor whether it is used this way. And that in turn raises a question: How? Because one of the core reasons this service is interesting is that it offers cheap calculation power. If you attach a metric ton of red tape and surveillance, it's most likely cheaper and faster to let your old Pentium do it.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
I hear that Chuck Norris just uses his name as the key. When anyone tries to crack it their computer catches fire.
The basic story is slightly hysterical. Firstly, WPA2 does use a multiple-iteration key derivation function. Secondly, even with the claimed performance, he can only "brute force" five or six characters, depending on the character set in use. It's enough performance to deal with dictionary words, because, indeed, it's a dictionary attack. But even at 400K password derivations per second (ie 400M SHA-1 hashes per second), eight random characters drawn from the 96 character printable ASCII repertoire are going to take 571 years to perform a brute force attack on, or an average time to success of 285 years. Don't like the odds? My home network uses 12 characters drawn from a 64 character set (ie base 64 encoding), which needs 374 million years (average 167 million) at that performance. Do I give a shit if that number gets reduced by a few orders of magnitude? Not really: I can always move to 15 characters...
...should Amazon and other public-cloud service providers [be liable for] customers [...] using their services to commit crimes?
Hope this helps...
XKCD:Xeric Knowledge Comically Dispen
The assertion that high end Tesla cards (often $2k) are required for this crack is nonsense. In terms of integer, single precision floating point and memory bandwidth, a GTX 580 is actually FASTER than the most expensive Tesla card. Tesla cards have better QA for 24/7 usage, 4x faster double precision floating point, and 3 or 6 GB of memory, plus some other occasionally useful features. But anyone with an NVIDIA SLI gaming rig built in the last 2 years could easily have done what this guy did in less than 20 minutes.