Re:Yahoo discloses hack of 1B accounts
by jsjohnst on Wednesday December 14, 2016 @07:42PM
(#13181254)
Oh, of course md5 has collisions. It's relatively easy (not computationally easy, but there are known methods) to find two random strings that hash to the same value, it's just very difficult to find a string that hashes to the value of a specific other string.
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Re:Yahoo discloses hack of 1B accounts
by schoen on Wednesday December 14, 2016 @09:24PM
(#13181839)
Not "relatively easy" by chance: it should require 2βΆβ΄ entries in your database to see a single collision happen at random! It's only "relatively easy" following cryptographic research in the early 2000s that exploits structure in MD5 to produce collisions deliberately.
Yes, collisions are easier than preimages, but they still shouldn't occur by chance in real applications!