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Re: DO NOT OPEN PREVIOUS MAIL Re: [oss-security] Denial of service in GnuPG


From: Tavis Ormandy <taviso () gmail com>
Date: Wed, 6 Jul 2022 06:10:32 -0000 (UTC)

On 2022-07-04, Jakub Wilk wrote:
As a data point, if Mutt has pgp_auto_decode=yes ("automatically attempt 
to decrypt traditional PGP messages") in the config, it will trigger the 
DoS when you view the message.

Hmm - I think you don't even need auto_decode, because x-action parameters
can trigger automatic decryption in mutt.

There's an example message here: https://gitlab.com/muttmua/mutt/-/issues/405

(And it seems that if you lose patience waiting for the message to show 
up and press ctrl+backslash in attempt to make it quit, it will actually 
hang forever.)


I think you need at least something like max-output 104857600 in
gnupg.conf if you don't want trivial DoS pranks to be possible :)

Tavis.


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