Re: [DNSOP] on staleness of code points and code (mentions MD5 commentary from IETF98)

Evan Hunt <each@isc.org> Tue, 28 March 2017 20:57 UTC

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Date: Tue, 28 Mar 2017 20:57:08 +0000
From: Evan Hunt <each@isc.org>
To: dnsop@ietf.org
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Subject: Re: [DNSOP] on staleness of code points and code (mentions MD5 commentary from IETF98)
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Earlier today Petr Špaček sent me an off-list comment that he intended
to be on-list, and I want to promote it:

On Tue, Mar 28, 2017 at 05:20:52PM +0200, Petr Špaček wrote:
> Here I have to agree with enforcing "MUST NOT". MD5 is a risk even on
> the validating side. It might provide attacker with ability to forge
> TLSA records in zones signed with MD5, which is has much worse
> consequences than treating the zone as unsigned. It is a security
> nightmare because validators supporting MD5 will treat this as valid and
> happily accept forged certificates!
 
This is a convincing argument, and I'm reconsidering my objections in
light of it.

-- 
Evan Hunt -- each@isc.org
Internet Systems Consortium, Inc.