Malicious PDF — malware analysis report

Static analysis result for SHA-256 275d4c671f334e43…

MALICIOUS

PDF

21.4 KB
MD5: f79249aacc2dbf0d8a5bb1f905d3fdfb SHA-1: 7b9491c9267836ac49e163d366afadcdf49632cc SHA-256: 275d4c671f334e4356c8ba98e10a028666cf189813a5776c36d2d5423871985d
108 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1204.002 Malicious File

The PDF document contains embedded JavaScript and triggers CVE-2009-4324 via the media.newPlayer API. The embedded JavaScript, particularly in legacy_pdfkit_stage_000.js, appears to be obfuscated but is indicative of a downloader or exploit execution stage. The ML classifier strongly flagged this PDF as malicious. The primary attack vector is the exploitation of a known PDF vulnerability.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • 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.
  • 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_obj0008_000.js
338b0ae080f7fcd96bd38c8b37953938ca6beb800b0244c0e80556bce94ef498
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2205 bytes
legacy_pdfkit_stage_000.js
c3df0b6d669953258363ab802ac0d32c63d5685d76eb2e0ad1f70f86b924f691
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xAB8 1256 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
42025b552c7960b53abcd8cd732b01c8d109eccfdfefc352b9826c4d5807d414
deobfuscated-js cross-stage annotation API aliases at offset 0x1E7 81 bytes