Re: CVE assignments for "weak" crypto (was CVE Request: MD5 used for Download verification)

[Kurt Seifried <kseifried () redhat com>]

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On 03/12/2013 09:36 AM, Christey, Steven M. wrote:
> All,
>
> This is an informal response, but I wanted to get something out
> pretty quickly.
>
> For CVE, our default position is that "using MD5 for integrity
> checking of downloads" is a security-hardening issue, and thus
> should NOT receive a CVE ID.  While MD5 may be "broken" from a
> theoretical standpoint, and there have been some demonstrations of
> collisions, and stronger options exist - I do not know of any
> reliable means of efficiently generating a collision that would
> also remain a functioning executable.  There is also a strong
> likelihood of debate as to which method is currently "strongest."

This is timely:

http://cr.yp.to/talks/2013.03.12/slides.pdf

one quote:

2012.06.07 Stevens: "A chosen-
prefix collision attack against
MD5 has been used for Flame.
More interestingly ... not our
published chosen-prefix collision
attack was used, but an entirely
new and unknown variant."

CrySyS: Flame file wavesup3.drv
appeared in logs in 2007; Flame
"may have been active for as long
as five to eight years".



- -- 
Kurt Seifried Red Hat Security Response Team (SRT)
PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993
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