The Story of Alice and her Boss (Real Life ™ Collision in MD5)
Differentiating from the usual stories about finding attacks on some algo that works in 2^127 instead of 2^128, these guys claim to have calculated in several hours (not years!) two postscript files with identical MD5. While waiting for more Real Life ™ stories of hell breaking loose due to hacked signed GNU/Linux binaries or whatever, read the story of Alice and her Boss (Hey, politically correct zealots, why not Andrew and his Bossess?)
[…] Astrology and Other Hash Functions for the Masses Filed under: General, Programming — Mordred @ 22:01 (A short explanation for noncoders and other muggles) A hash function is a method for reducing an arbitrary long piece of data into a smaller, fixed-size piece, with the added bonus that the smaller piece will be a sorta kinda unique representation of the long piece. Because of the assumed uniqueness, often the hash value is used as an identifier of the long piece of data. That’s not generally true of course, you can’t shrink a book to one word, and hope that no other book will shrink to that same word. But, if you want to compare two books and their corresponding “hash words” are different, you can be absolutely sure that the books are different as well, and skip the lengthy word-for-word check. If the hash values are the same, we call it a collision. In cryptographic applications the collisions may be a bad thing, while in other scenarios, they are merely a nuisance (depends on how you choose to decide if two things are the same or not). This explanation is beginning to steer away from the purpose of the article, so it will stop HERE. […]
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