analyzing-malicious-pdf-with-peepdf

# Analyzing Malicious PDF with peepdf ## When to Use - When triaging suspicious PDF attachments from phishing emails - During malware analysis of PDF-based exploit documents - When extracting embedded JavaScript, shellcode, or executables from PDFs - For forensic examination of weaponized document artifacts - When building detection signatures for PDF-based threats ## Prerequisites - Python 3.8+ with peepdf-3 installed (pip install peepdf-3) - pdfid.py and pdf-parser.py from Didier Stevens suite - Isolated analysis environment (VM or sandbox) - Optional: PyV8 for JavaScript emulation within peepdf - Optional: Pylibemu for shellcode analysis ## Workflow 1. **Triage with pdfid**: Scan PDF for suspicious keywords (/JS, /JavaScript, /OpenAction, /Launch, /EmbeddedFile). 2. **Interactive Analysis**: Open PDF in peepdf interactive mode to explore object structure. 3. **Identify Suspicious Objects**: Locate objects containing JavaScript, streams, or encoded data. 4. **Extract Content**: Dump suspicious streams and decode filters (FlateDecode, ASCIIHexDecode). 5. **Deobfuscate JavaScript**: Analyze extracted JS for shellcode, heap sprays, or exploit code. 6. **Check VirusTotal**: Use peepdf vtcheck to cross-reference file hash with AV detections. 7. **Generate IOCs**: Extract URLs, domains, hashes, and shellcode signatures. ## Key Concepts | Concept | Description | |---------|-------------| | /OpenAction | Automatic action executed when PDF is opened | | /JavaScript /JS | Emb...