Cracking Passwords In The Cloud: Amazon’s New EC2 GPU InstancesHacker uses cloud computing to crack passwords
A German hacker claims to have used cloud computing to crack passwords
stored in an algorithm that was developed by the NSA.
Hacker Thomas Roth announced on Tuesday that he has used one of Amazon
Web Service's Cluster GPU Instances to crack the passwords encrypted in a
Secure Hashing Algorithm (SHA1) hash.
"I think that cloud cracking can be useful in the future because of its massive
parallel nature. You can start a 100 node cracking cluster with just a few clicks,"
Roth told ZDNet UK on Tuesday.
"GPUs are known to be the best hardware accelerator for cracking passwords, so
I decided to give it a try: How fast can this instance type be used to crack SHA1
hashes? Using the [Cuda-Multiforcer], I was able to crack all hashes from [the
560 character SHA1 hash] with a password length from one to six in only 49
minutes (one hour costs $2.10 [£1.30] by the way)," Roth wrote on his blog.
A SHA1 hash is an encryption algorithm. SHA1 is vulnerable to a brute-force
attack, which is the same technique as the Multiforcer that Roth employed. This is
a technique where computers are used to repeatedly attempt to crack a password
by successively trying varying combinations of numbers and digits.
The Cluster GPU Instance is built around two Nvidia Tesla Fermi-architecture
GPUs. Tesla uses Cuda, an Nvidia-developed software interfacing architecture
that allows code to be written for the Tesla GPU that ekes out maximum
performance from the underlying hardware. Roth used a Cuda-specific script to
increase the effectiveness of his hack, he wrote.
Roth told ZDNet UK that to be suitable for computation on Cuda, tasks must be
able to be broken down into many smaller tasks that do not need to share data
with each other and can run in parallel.
Since 2005, SHA1 has also been vulnerable to an attack that is 2,000 times as
effective as a brute-force attack.
In May Verisign reported that botnets were available for hire for as little as
$8.94 an hour to carry out cybercrimes.
SHA1 is a hashing algorithm, not an encryption algorithm, as was first reported in
this article. SHA1 generates a 160-bit hash of a message. Roth's cloud cracking
experiment worked by working through all inputs to create the same output as the
original SHA1 hash.
GPUs are known to be the best hardware accelerator for cracking passwords, so I decided to give it a try: How fast can this instance type be used to crack SHA1 hashes?22 GB of memory
33.5 EC2 Compute Units (2 x Intel Xeon X5570, quad-core “Nehalem” architecture)
2 x NVIDIA Tesla “Fermi” M2050 GPUs
1690 GB of instance storage
I/O Performance: Very High (10 Gigabit Ethernet)
API name: cg1.4xlarge
# wget http://developer.download.nvidia.com/compute/cuda/3_2/sdk/gpucomputingsdk_3.2.12_linux.run # chmod +x gpucomputingsdk_3.2.12_linux.run # ./gpucomputingsdk_3.2.12_linux.run (Just press enter when asked for the installation directory and the CUDA directory.)
# yum install automake autoconf gcc-c++
# cd ~/NVIDIA_GPU_Computing_SDK/C/ # make lib/libcutil.so # make shared/libshrutil.so
# cd ~/NVIDIA_GPU_Computing_SDK/C/ # wget http://www.cryptohaze.com/releases/CUDA-Multiforcer-src-0.7.tar.bz2 -O src/CUDA-Multiforcer.tar.bz2 # cd src/ # tar xjf CUDA-Multiforcer.tar.bz2 # cd CUDA-Multiforcer-Release/argtable2-9/ # ./configure && make && make install # cd ../
CCFILES := -largtable2 -lcuda
LINKFLAGS := -largtable2 -lcuda
# export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH # export LD_LIBRARY_PATH=/usr/local/cuda/lib64:$LD_LIBRARY_PATH # cd ~/NVIDIA_GPU_Computing_SDK/C/src/CUDA-Multiforcer-Release/ # ../../bin/linux/release/CUDA-Multiforcer -h SHA1 -f test_hashes/Hashes-SHA1-Full.txt --min=1 --max=6 -c charsets/charset-upper-lower-numeric-symbol-95.chr