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Malicious office doc with process hollowing shellcode

Introduction  This post covers how to identify and extract shellcode manually from hancitor phishing office document. 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   SHA256:  5d077b1341a6472f02aac89488976d4395a91ae4f23657b0344da74f4a560c8d   This sample contains encoded shellcode that starts a new (suspended) explorer.exe process, injects its own code (an embedded, encoded exe) and executes it.  This maldoc leverages  VBA macros  to execute its payload  and t he encoded shellcode is a property in stream 17.  T he shellcode uses WIN32 API functions like CreateProcess, ZwUnmapViewOfSection, GetThreadContext, ResumeThread etc. to inject code into the newly created process (explorer.exe) and execute it. This method is called process hollowing or process replacement.The explorer.exe process is created in a suspended state, the code for explore

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 o ledump.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 4

Malicious document analysis Part-2

Introduction  A basic and quick approach to analyse phishing documents to identify indicators of maliciousness. Refer Part-1  to understand the tools and approach to analyse office word document. This post covers the  static analysis of pdf document to identify suspicious objects. (FYI  running pdf in sandbox environment can give much insight related to indicators of compromise.)  FYI this post doesn't cover complete & in depth analysis (like dealing with malicious obfuscated javascripts or shellcode)  of malicious documents Tools peepdf Didier Stevens Suite    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: 93fc24573bd563f08b3a6a71276bfe085488d3bbb8d79bbbc3a75e5c0497e915              6256dead623ef48c9506e9d5dd92227c59f92828cff610a093b956f3bd7284c2 To analyse PDF files,  open them in a hex

Malicious document analysis Part - 1

Introduction  A basic and quick approach to analyse phishing documents to identify indicators of maliciousness. FYI this post doesn't cover complete & in depth analysis of malicious documents Tools  Didier Stevens Suite   sudo pip install oletools  Yara - A pattern matching Swiss knife  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 1:  e07c84f98332b07ae40a22f15c32cbf794586e26576a7539def667881e15beae Download above mentioned sample and check the integrity Check the file properties using native Linux file command which gives quick idea about sample Download Didier Stevens Suite and check for yara rules. Run various rules against the sample document to identify any sort of maliciousness The below rule can identify an executable file embedded in OLE objects  Run above yara rule against the

Memory dump analysis of Donny's System

Introduction  This post solves the mystery of Donny's System   and outlines how to utilize memory forensics methodology to uncover artifacts from memory dumps Tools: Volatility, Yara  & Windows Powershell Analysis Six-step investigative methodology by SANS Identify rogue processes  Analyze process DLLs and handles   Review network artifacts  Look for evidence of code injection  Check for signs of rootkit Dump suspicious processes and drivers  Run volatility  imageinfo plugin   to identify profile  PS C:\volatility> .\vol.exe -f .\unknown.vmem imageinfo Run Volatility  pslist plugin to see active running processes PS C:\volatility> .\vol.exe -f .\unknown.vmem --profile=WinXPSP3x86 pslist Just to remind that all process creation and termination timings are specified in UTC. Ensure to change them to system timezone while correlating the events with other sources of evidence game.exe clearly looks suspicious as it ran and exit in a short span o