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Re: [ietf-822] one can re-sign without a permission to re-sign header

"John R Levine" <johnl@taugh.com> Fri, 02 May 2014 14:42 UTC

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Date: Fri, 02 May 2014 10:42:32 -0400
Message-ID: <alpine.BSF.2.00.1405021036010.79573@joyce.lan>
From: John R Levine <johnl@taugh.com>
To: Pete Resnick <presnick@qti.qualcomm.com>
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Archived-At: http://mailarchive.ietf.org/arch/msg/ietf-822/L1OjorjGL5ILaBqfBDBMtZZU2rw
Cc: ietf-822@ietf.org
Subject: Re: [ietf-822] one can re-sign without a permission to re-sign header
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> I don't see any replay protection in here at all. Nothing that says to keep 
> the signature expiration relatively short, and nothing which a mailing list 
> recipient could not subsequently use to send spam. The first issue just needs 
> a mention. It's the second issue that needs to be addressed IMO:

Yeah, that occurred to me about five minutes after I posted it.  Here's a 
tweaked version where the mf tag is now mf=list.domain, with handwaving 
about how a may-forward signature doesn't count unless there's also a 
signature from the list domain.  Given lengthy discussions about how 
little abuse comes from real mailing lists, that'd probably be adequate.

http://datatracker.ietf.org/doc/draft-levine-may-forward/

> I wouldn't bother with what you've proposed.

Neither would I.  Whitelisting solves this problem far better.

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
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