In my blog post “Quickpost: Analysis of PDF/ActiveMime Polyglot Maldocs” I explain how to search through MIME files with my tool emldump.py to find suspicious/malicious content:
I have now released a new version of emldump.py, that can output the content of all parts in JSON format.
This is done with option –jsonoutput:
This JSON output can then be consumed by different tools I develop. One of them is file-magic.py, a tool to identify files using the libmagic library.
Here file-magic.py identifies all parts of the MIME file:
And it becomes clear that the JPEG parts is not actually an image, but an MSO/ActiveMime file that can contain VBA code.
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