Single-block collision for MD5

Re:Single-block collision for MD5 by andrewcooke on Sunday January 29, 2012 @01:33PM (#3525770)

can you clarify what you mean by "plain md5"? if someone is using md5 with crypt(3) is that ok?

i ask because of this - https://bugzilla.novell.com/show_bug.cgi?id=743715

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Re:Single-block collision for MD5 by michaelfairley on Sunday January 29, 2012 @02:52PM (#3525980)

http://codahale.com/how-to-safely-store-a-password/

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Re:Single-block collision for MD5 by riffraff on Sunday January 29, 2012 @04:33PM (#3526339)

AFAIK crypt(3) should not be using "plain" md5, it uses both a salt and variations of md5, plus the hash function is run many times so that bruteforce attacks are mitigated (it takes much more time to compute the hashes)

googling..... http://en.wikipedia.org/wiki/Crypt_(Unix)#MD5-based_scheme

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Re:Single-block collision for MD5 by flixic on Sunday January 29, 2012 @01:37PM (#3525779)

I think teraflop had in mind salting.

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Re:Single-block collision for MD5 by dodedo on Sunday January 29, 2012 @02:33PM (#3525913)

A salt only protects against pre-computed dictionary attacks (rainbow tables). It does not offer any additional protection in this scenario.

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Re:Single-block collision for MD5 by EGreg on Sunday January 29, 2012 @02:23PM (#3525885)

I would recommend both salting and key strengthening.

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Re:Single-block collision for MD5 by JoachimSchipper on Monday January 30, 2012 @03:36AM (#3527950)

It's not best practice (use bcrypt/PBKDF2/scrypt), but there are no known or suspected attacks on that construction and the original article does not seem likely to help in finding one.

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