Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 05 Nov 2014 04:45:46 +0000
From: Alex Gaynor <alex.gaynor@...il.com>
To: oss-security@...ts.openwall.com
Subject: Re: is MD5 finally dead?

As far as I can tell, HMAC doesn't actually require pre-image resistance,
it requires that the compression function used by the has be a PRF -- or at
least that's what the HMAC paper says. Are these two formulations
equivalent?

Alex

On Wed Nov 05 2014 at 8:42:59 PM Michael Samuel <mik@...net.net> wrote:

> Hi,
>
> On 5 November 2014 15:21, Kurt Seifried <kseifried@...hat.com> wrote:
> > http://natmchugh.blogspot.co.uk/2014/10/how-i-created-two-
> images-with-same-md5.html
> >
> > It seems like MD5 should probably be classed with DES as instant CVE
> > win, either now, or pretty soon....
>
> This is the same chosen-prefix attack that was used to forge
> certificates.  Using md5 in
> a collision-hostile environment is definitely CVE worthy, and has been
> for a while. (BTW,
> no CVE for rsync yet)
>
> In the case of an unknown-prefix, HMAC[1] or anything requiring a
> preimage, it's
> just hardening to use swap out MD5 (and SHA-1).
>
> [1] Unless you accidentally swap the key and data fields!
>

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.