Didier Stevens

Tuesday 22 December 2015

MIME File With “Header”

Filed under: maldoc,My Software — Didier Stevens @ 0:00

I’m providing a 2-day training at Brucon Spring Training 2016: “Analysing Malicious Documents“.

Malicious MS Office documents are also distributed as MIME files. A blog reader asked for help with a MIME file that gave him problems: f67aa5a3ede3d31c5a68494c0678e2ee.

Accoring to emldump.py, the file is just text (not a multipart file):

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But if you look at the file, you’ll notice a line preceding the MIME-Version line:

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You can instruct emldump to skip this line with option -H:

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Now emldump is able to analyze the multipart MIME file, and detect the MSO file (part 3). oledump can analyze MSO files:

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