Malicious PDF — malware analysis report

Static analysis result for SHA-256 5018c236ed06df63…

MALICIOUS

PDF

11.9 KB
MD5: e933fd18afd33319b98acbb0f7eba57f SHA-1: f3b6dc760b2646cd5c76a30f674c9cdbf5339a14 SHA-256: 5018c236ed06df635ecc5ac317b7abecab00e180534347db3730625795a4e37a
146 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link or Macro: Malicious Link

The PDF sample contains embedded JavaScript that exploits CVE-2007-5659, specifically targeting the Collab.collectEmailInfo function. Static analysis recovered two deobfuscated JavaScript files, legacy_pdfkit_stage_000.js and legacy_pdfkit_stage_001.js, indicating a multi-stage attack. The primary function of the embedded script appears to be downloading and executing a second-stage payload, consistent with a typical exploit kit delivery mechanism.

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
8a8df6b2c11289bb6697bd25e702249e36215f9853f84e7fc0bf9c04232223c0
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 5074 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
e912281460f947031da011bc0332463c2aff5afdb6b0f720d64fbf627ee54991
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 11973 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).