[Esd-l] MIME types and magic

John D. Hardin jhardin at impsec.org
Sun Sep 8 09:04:01 PDT 2002


I just got a message that had an attachment with MIME type
"application/octet-stream" named "whatever.gif" (the actual name part
doesn't matter, but the .gif is significant).

It wasn't, of course, sanitized, since .GIF is considered "safe".

The attachment was actually a Windows executable.

Is Windows checking file magic on generic MIME types? I wouldn't
expect this to be a successful attack if Windows fires off an image
viewer based on the filename.

 John Hardin KA7OHZ    ICQ#15735746    http://www.impsec.org/~jhardin/
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