Re: security fixes (KDF, MDC->MAC)?

disastry@saiknes.lv Fri, 27 September 2002 08:16 UTC

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Date: Fri, 27 Sep 2002 10:05:51 +0200
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Subject: Re: security fixes (KDF, MDC->MAC)?
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> Hello OpenPGP,
> 
> Is there interest in fixing the security flaws discussed in the recent
> "security analysis" thread? -
> 
> (1) the Integrity Protected Data and MDC Packets fail to stop Schneier et
> al's attack, because the ciphertext blocks can be pasted into a
> non-integrity protected packet (ie ciphertext from a tag 18 packet can be
> placed in a tag 9 packet, evading the MDC).

5.13.
[...]    Unlike the Symmetrically Encrypted Data Packet, no
   special CFB resynchronization is done after encrypting this prefix
   data.

doesn't this prevent converting packet 18 to 9 ?

__
Disastry  http://disastry.dhs.org/
http://disastry.dhs.org/pgp
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