Re: Report of collision-generation with MD5

From: Claudiu (dr.clau_at_rdslink.ro)
Date: 08/18/04

  • Next message: Mike Tancsa: "Re: Report of collision-generation with MD5" 
    Date: Wed, 18 Aug 2004 21:08:12 +0300
To: "Peter C. Lai" <sirmoo@cowbert.net>, freebsd-security@freebsd.org

    hello,

    please explain what do you mean by "reverse the hash". Is this the
    recreation of the originial message from its hash ?

    With respect,

    Peter C. Lai wrote:
    > Well while collisions are cryptographically significant, they don't
    > necessarily impact any operational security of the the hash. (Since the
    > collision merely means that there are possibly two inputs which will hash to
    > the same digest). Where this could theoretically mean that someone could
    > alter a signed message, we have to look at the chance that what was intended
    > to be altered will satisfy the conditions for the collision. The only 'real'
    > worry about this issue is that if MD5 is already cryptographically challenged
    > in this manner, it may be more possible to find a way to reverse the hash.
    >
    > You can read the discussion here:
    > http://www.rtfm.com/movabletype/archives/2004_08.html#001053
    > http://www.rtfm.com/movabletype/archives/2004_03.html#000820
    >
    > On Wed, Aug 18, 2004 at 10:24:27AM -0700, David Wolfskill wrote:
    >
    >>Just got a pointer to this via ACM "TechNews Alert" for today:
    >>
    >>http://www.acm.org/technews/articles/2004-6/0818w.html#item2
    >>
    >>Seems that "... French computer scientist Antoine Joux reported on
    >>Aug. 12 his discovery of a flaw in the MD5 algorithm, which is often
    >>used with digital signatures...."
    >>
    >>There's more in the article cited above.
    >>
    >>Peace,
    >>david
    >>--
    >>David H. Wolfskill david@catwhisker.org
    >>Evidence of curmudgeonliness: becoming irritated with the usage of the
    >>word "speed" in contexts referring to quantification of network
    >>performance, as opposed to "bandwidth" or "latency."
    >>_______________________________________________
    >>freebsd-security@freebsd.org mailing list
    >>http://lists.freebsd.org/mailman/listinfo/freebsd-security
    >>To unsubscribe, send any mail to "freebsd-security-unsubscribe@freebsd.org"
    >
    > 

    -- 
Claudiu Dragalina-Paraipan
e-mail: dr.clau@rdslink.ro
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  • Next message: Mike Tancsa: "Re: Report of collision-generation with MD5"

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