A Study of the Collision Cryptanalysis against MD4 and MD5

• Main Authors: Guan-Ting Chen, 陳冠廷
• Other Authors: Wen-Guey Tzeng
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/60819472084515498599

碩士 === 國立交通大學 === 資訊科學與工程研究所 === 94 === In EuroCrypt2005, Wang et al. publish their collision searching algorithms for MD4 and MD5. Many researchers follow their results and publish their improvements on the collision searching algorithms. Many of them focus on how to do the message modification efficiently. In this thesis, we improve the message modification techniques. We use our message modification methods to satisfy 1 sufficient condition in the first iteration and 5 sufficient conditions in the second iteration for MD5. For MD4 collision searching algorithm, we correct the errors in the previous results. We implement the collision searching algorithm for both MD4 and MD5. Our implementation of the MD5 collision searching algorithm takes about 1.75 hours to give a collision pair in average. The successful probability to find the collision pair in 12 hours is 1 according to our experiments.