Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb88a5ec894a9a0f…

MALICIOUS

PDF

12.4 KB
MD5: 572ccf6d39318764127df5ad9a42bd2c SHA-1: b42c3dfa5534961785e4f169564e445514533354 SHA-256: cb88a5ec894a9a0f9ba6a4e0ae860cb6c0af9c9a018f2e382113603f604f7588
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 used to deobfuscate and execute further stages, likely downloading and running a second-stage payload. The presence of 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js' further supports this, suggesting a multi-stage attack. The exact nature of the payload cannot be determined from the provided evidence.

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
2d676786465676f828d5e6d62a54f86613af2987e81d8329035a8979de3b34f6
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 5297 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
9a2b50956636d20250083645bf4da8c18c7f977be7015e6e3275b72fdc54b6de
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 12561 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).