Malicious PDF — malware analysis report

Static analysis result for SHA-256 91d08fb5eb7e49a1…

MALICIOUS

PDF

11.7 KB
MD5: 16568a6122b0e8cd325e35edc8557445 SHA-1: ba2ad5f64182cc0dd2f2fc4f28c22498953a815a SHA-256: 91d08fb5eb7e49a192d3da11aaf09c0aab31096e9232a27171454f7dc42a3b28
146 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains embedded JavaScript that exploits CVE-2007-5659, specifically targeting the Collab.collectEmailInfo function. The heuristics indicate that this JavaScript is encoded and is likely responsible for downloading and executing a second-stage payload. The presence of deobfuscated JavaScript files further supports this, suggesting a multi-stage attack. The ClamAV detection also confirms the malicious nature of the file.

Heuristics 6

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-35903 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35903
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
860eae5f96eb426380281c575a089242b50523bbb4bbb8dd765e582cd9c07d2e
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 294 bytes
legacy_pdfkit_stage_000.js
b935569df91c7c784abfb9e63653628fe65597208e8501b25155f0ee34b41521
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 4922 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
35a71e7a3c2c0abc7b67bf4de6da85afe118628db70b1766f70e55c510305d8b
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 11892 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).