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On 27/01/12 18:29, Irving Reid wrote:
<blockquote class=" cite" id="mid_4F22ED10_7000405_mozilla_com"
cite="mid:4F22ED10.7000405@mozilla.com" type="cite">Any
modifications you make to a message in your (received) copy would
cause the sender's signature to no longer match, so it will be
obvious that the receiver's copy isn't what the sender signed.
<br>
<br>
While I haven't looked into Outlook's signing, there's no way for
it to permanently alter a message and keep the existing signature.
They may be doing something like "person A signed the original
content of the message, and person B altered the message and
signed the altered version" but there's no way to make it appear
that person A signed the altered version unless you have person
A's private key.
<br>
<br>
- irving -
<br>
</blockquote>
<br>
Does this also apply to header fields? I would really be interested
in the edge case of the ISP modifying the subject lines or from
Address (as certain SMTP servers would do). Would this also change
the signature, or is this message body only?<br>
<br>
Axel<br>
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