Malicious office document analysis Part-3

Introduction
This post covers how to identify and extract potential malicious content like embedded executable and payloads from Macro forms in office documents. Refer Part-1 and Part-2 to get an understanding of tools and approach to analyse phishing documents.

Tools

Didier Stevens Suite
sudo pip install oletools

Analysis

All document samples are pulled from Hybrid Analysis - a free malware analysis service for the community that detects and analyzes unknown threats using a unique Hybrid Analysis technology.

Hash: 345b804a9416595840516674caaa65e65be57591d300beab2b6190298a9eac78

Download above mentioned sample and check the integrity

Check the file properties using native Linux file command which gives quick idea about sample

Ran oledump.py to check the embedded macros and macro related forms

It was found that stream 14 and 15 look like macro forms. Dump them using -d option to check anything suspicious content in it

Wow ! Hex 4d5a was observed which is traditional ASCII MZ header for windows executable, DLL or sys files. Ran base64dump.py to decode the hex coded content to check the ASCII header

Dumped the identifier 1 in ASCII

Ran pecheck.py to check the PE file basic properties, history, header, sections info, imports and exports

Dump the PE file for further analysis

Comments

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