PGP sign highlight on mutt

From: Ademar de Souza Reis Jr. (ademarat_private)
Date: Wed Oct 24 2001 - 07:38:58 PDT

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    Hi there.
    
    When you receive a PGP signed message on mutt (a very popular text
    based mail client), there are some ways you know it's signed:
    
    1. The flags "s" or "S" in the message index (and in the bottom of a msg)
    2. A message like "PGP signature successfully verified" in the bottom when
       opening a message
    3. A *highlighted* message body with the gpg output (example given below)
    
    "
    
    [-- PGP output follows (current time: Tue 23 Oct 2001 05:10:41 PM BRST) --]
    gpg: Warning: using insecure memory!
    gpg: Signature made Tue 23 Oct 2001 04:35:11 PM BRST using DSA key ID 825F1270
    gpg: Good signature from "Ademar de Souza Reis Junior <ademarat_private>"
    [-- End of PGP output --]
    
    [-- The following data is signed --]
    
    Hi there.
    
    []'s
       - Ademar
    
    [-- End of signed data --]
    "
    
    The point here is that since the most notorious one is (3), you can
    copy&paste it in a message body (change times and some details) and
    let mutt users think a message is signed when it's not.
    
    In fact, I did it here in the company I work for. Since almost everybody
    uses mutt in my department, it was easy to send a message with the
    "From: " adultered and "signed" as the boss. (Yes, the boss didn't like
    it, but he understood since I explained it was a "proof of concept") :)
    
    Yes, you can consider this just a "human mistake", a "social exploit"
    or whatever you want, but I think mutt could help avoiding that easily:
    
    It could highlight the text only when it cames from gpg and not
    every time it appears in the message body
    or
    It could interact with gpg in some other (better) way.
    or
    [put your solution here]
    
    BTW, does that "vulnerability" applies to other mail clients too?
    
    []'s
       - Ademar
    



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