Malicious PDF — malware analysis report

Static analysis result for SHA-256 529a813e1874dd2a…

MALICIOUS

PDF

21.4 KB
MD5: df8620356a7a293901c5f046208807a4 SHA-1: 8fd2165ba0dfd5518fbd49de99776f7c2b91e112 SHA-256: 529a813e1874dd2ada68ffe63de4c0fa116e6f21f4ef028f878f953c2525452d
108 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, flagged by multiple heuristics including a critical alert for CVE-2009-4324 (media.newPlayer). The ML classifier strongly indicates maliciousness. The JavaScript is obfuscated but appears designed to exploit this vulnerability, likely to download and execute a second-stage payload. The presence of 'legacy_pdfkit_stage_000.js' suggests a known PDF exploitation kit.

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
1496c93983480c6dc81a05bc5ba857eab6cc42c47d120778716522754b591fc8
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