Algebraic Cryptanalysis of 58-Round SHA-1

In 2004, a new attack against SHA-1 has been proposed by a team leaded by Wang [15]. The aim of this article5 is to sophisticate and improve Wang’s attack by using algebraic techniques. We introduce new notions, namely semi-neutral bit and adjuster and propose then an improved message modification technique based on algebraic techniques. In the case of the 58-round SHA-1, the experimental complexity of our improved attack is 231 SHA-1 computations, whereas Wang’s method needs 234 SHA-1 computations. We have found many new collisions for

• Type: Conference
• Year: 2007
• Where: FSE
• Authors: Makoto Sugita, Mitsuru Kawazoe, Ludovic Perret, Hideki Imai
• Keywords: Algebraic Techniques, Cryptography, FSE 2007, SHA-1, SHA-1 Computations