procmail
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Re: Help! Need to use procmail to fight dangerous security exploit

1998-08-18 10:21:49
So the MUA software that is used to display the MIME message is the
culprit. I Use Emacs to handle MIME, so it has no such threats, so poor
Microsoft software may get upset and allocate too little space.

Yes, it's the MUA...  Although the LDA could run into problems as
well if it were processing MIME.  So far Eudora, Netscape Mail,
Outlook Express, and mutt (Unix) have all been found to have
buffer overflow problems.

So, this has nothing to do with mail or it's content. Procmail can
handle as big messages as you have system and virtual memory. The
only thing you can make Procmail overflow is, when you try to match 
too much and your LINEBUF setting is too short. Bute then you made it
to happen yourself :-)

As Philip said earlier, it's the only *known* condition that can make procmail 
overflow.  Doubtless there are other overflow possibilities that have yet
to be discovered...  Remember, there are no absolutes.  Absolutely.

I've been plugging through the code trying to find exploits, but being
on vacation and all I wasn't very inspired.  I'll keep looking.

As an aside (and probably more on-topic), has anyone ever tried compiling
procmail with checkergcc?  It's an excellent GPL memory checking mechanism
a la Purify, but I've never been able to compile procmail with it.  Works
with every other program that I've ever tried, though.

Chris