• Tag Archives cryptography
  • Cryptographers Demonstrate Collision in Popular SHA-1 Algorithm

    On February 23rd, a joint team from the CWI Amsterdam and Google announced that they had generated the first ever collision in the SHA-1 cryptographic hashing algorithm. SHA-1 has long been considered theoretically insecure by cryptanalysts due to weaknesses in the algorithm design, but this marks the first time researchers were actually able to demonstrate a real-world example of the insecurity. In addition to being a powerful Proof of Concept (POC), the computing power that went into generating the proof was notable:

    We then leveraged Google’s technical expertise and cloud infrastructure to compute the collision which is one of the largest computations ever completed.

    Here are some numbers that give a sense of how large scale this computation was:

    • Nine quintillion (9,223,372,036,854,775,808) SHA1 computations in total
    • 6,500 years of CPU computation to complete the attack first phase
    • 110 years of GPU computation to complete the second phase

    The CWI Amsterdam and Google researchers launched