Password recovery software developers actively introduce general purpose computations on GPU (GPGPU) into their products. Today I will test three products, which already have support of NVIDIA and/or ATI cards for password recovery of Microsoft Office files.
Thus, here are three products:
- Accent Office Password Recovery v. 3.50, which supports both NVIDIA and ATI cards;
- Parallel Password Recovery (Office module) v. 1.5.1 (supports only NVIDIA GPU);
- Elcomsoft Distributed Password Recovery v. 2.90 with NVIDIA card support (Elcomsoft company has special product for password recovery of MS Office – AOPR, but it doesn’t have GPU support yet).
And three Office versions widely-distributed today: MS Office XP, 2007 and 2010.
It was taken two files for test of each version – one with standard key length (128 bit for all Office version) and one with non-standard key length (RC4 algorithm with 120 bit key for Office XP and AES with 256 bit key for Office 2007 and 2010).
Testing was made on typical modern computers, two of them were desktops and one was laptop:
- Intel Core i5-750 (2.66 GHz, 4 cores), NVIDIA GeForce GTX 260 (216 SP), 4 GB RAM, Windows 7 64-bit
- Intel Core 2 E6300 (1.8 GHz, 2 cores), NVIDIA GeForce 9800GT (112 SP),2 GB RAM, Windows XP 32-bit
- AMD Athlon II M300 (2.00 GHz, 2 cores), ATI Mobility Radeon HD 4300 (80 SP), 2 GB RAM, 64-ΒΙΤΞΑΡ Windows 7
Testing results are given below in the table (different computers are shown with different colors; in case where the test was made till the end it is shown both time and speed, in other case only speed is shown). Only brute force method was testing using lower-case letters and starting from one-symbol passwords.
|Accent Office PR||Parallel PR||Elcomsoft Distributed PR|
|Office XP, 128 bit||2.200.000 p/s, time – 2:25 (4 CPU, GPU not used)||9.000.000 p/s, time – 0:45 (3 CPU+1 GPU)||1.800.000 p/s, time – 3:00 (4 CPU, GPU not used)|
|not tested||5.600.000 p/s, time – 0:55 (1 CPU+1 GPU)||600.000 p/s, time – 8:20 (2 CPU, GPU not used)|
|600.000 p/s, time – 8:40 (2 CPU, GPU not used)||1.400.000 p/s, time – 4:06 (2 CPU, GPU not supported)||600.000 p/s, time – 8:32 (2 CPU, GPU not supported)|
|Office XP, 120 bit||has stopped working||5.000.000 p/s (4 CPU, GPU not used)||password not found|
|3.600.000 p/s (2 CPU, GPU not used)|
(2 CPU, GPU not supported)
|Office 2007, 128 bit||4600 p/s, time – 1:43 (3 CPU + 1 GPU)||4600 p/s, time – 1:42 (3 CPU + 1 GPU)||3600 p/s, time – 2:12 (1 GPU, CPU not used)|
|2900 p/s, time – 2:41 (1 CPU + 1 GPU)||2800 p/s, time – 2:48 (1 CPU + 1 GPU)||2600 p/s, time – 2:57 (1 GPU, CPU not used)|
|600 p/s, time – 13:43 (1 CPU + 1 GPU)||200 p/s, time – 40:00 (2 CPU, GPU not used)||140 p/s, time – 1 hour (2 CPU, GPU not used)|
|Office 2007, 256 bit||file not recognized||4600 p/s (3 CPU + 1 GPU)||password not found|
|Office 2010, 128 bit||2300 p/s (3 CPU + 1 GPU)||2300 p/s (3 CPU + 1 GPU)||1800 p/s, time – 4:24 (1 GPU, CPU not used)|
|1500 p/s (1 CPU + 1 GPU)||1400 p/s (1 CPU + 1 GPU)||1300 p/s (1 GPU, CPU not used)|
|300 p/s, time – 27:23 (1 CPU + 1 GPU)||100 p/s (2 CPU, GPU not used)||70 p/s (2 CPU, GPU not used)|
|Office 2010, 256 bit||file not recognized||2300 p/s (3 CPU + 1 GPU)||password not found|
Table. Password recovery speed of MS Office files on different CPU and GPU, passwords per second.
According to this empiric data it is possible to make several conclusions:
- MS Office password recovery utilities badly cope with non-standard encryption (non-standard key length) – file non-recognition and even program hang-up was mentioned. Even Parallel Password Recovery – the decisive leader, that found the right password of the all examples, in one of the cases did not use GPU at non standard 120-bit key length.
- Parallel Password Recovery software is also the leader on speed at password recovery of MS Office XP/2003 files, as it is the only one program that uses GPU in that case, but its speeds on CPU are impressive as well.
- In the case of standard MS Office 2007 and 2010 files all program speeds became nearly identical (EDPR lag connects with the fact that it didn’t use CPU and the recovery speed at GPU it has the same as the others). Such equality comes from the fact that these Office versions use special slow-down key derivation procedure (more specifically, 50.000 and 100.000 calls of SHA-1 hashing function), and all developers optimized this function up to the maximum long ago.
- Office 2010 password recovery speed is exactly two times smaller in all programs and any processing units (CPU and GPU) than Office 2007. It is directly connected with doubled count of SHA-1 calls. It is safe to say that encrypted Office 2010 files set new record in password recovery speed and provide with most strong encryption, decrown previous leader – encrypted RAR 3.x archives
- Accent Office Password Recovery program though badly copes with non-standard files, nevertheless excels with literate use of graphics processor: that is the only one program enabling more or less comfortably work on computer during password recovery on GPU (other programs hang up on few seconds before every screen refresh), also it is the only program that supports ATI, even such low-power as ATI Mobility Radeon HD 4300. By using GPU on third laptop AOFPR shows three times speed-up compared with other competitors.
Thank you to all companies providing me with registration keys for their products – true speed testing would have been impossible without them. In future I plan to continue password recovery programs testing – all concerned developers please contact me by e-mail.