Study on GPU-based password recovery for MS Office2003 document

Analyzing the document structure and encryption mechanism of Microsoft Office2003, we designed the password recovery experiments on both CPU and CUDA platform, and then discussed the security with time consumption as the indicator. The GPU's multicore and multithread structure makes it very suitable for executing parallel task, thus greatly accelerated the password exhaustively speed, the time cost for password exhaustively on CPU can be reduced more than 10 times at least, taking advantage of the GPU acceleration. The three kinds of encryption scheme supported in MS Office2003 all lack of necessary iterative operation, so that its safety is hard to ensure when facing the increasingly powerful computing capabilities and parallel technology.