Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7ba8ba7fa179e76…

MALICIOUS

PDF

43.2 KB
MD5: d85ad3106722c09d36bcfabaa399972b SHA-1: 7731815458016d5ea933929a1270982ce15564af SHA-256: f7ba8ba7fa179e7685b0e0f9104e89312b530b6cde078fa76348d467f1f0137b
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 ML classifier strongly indicates maliciousness. The embedded JavaScript, particularly in legacy_pdfkit_stage_000.js, appears to be obfuscated and likely responsible for downloading and executing a secondary payload, though the exact URL or payload could not be fully reconstructed due to obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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
3787394029668d2946feca1e6f7f86e953d9ef553c1124d7a749c0939e05d379
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2205 bytes
legacy_pdfkit_stage_000.js
e25eb9dea927fc4a67324232040e7bccd1874be12a367fce24d0ca6ae7a3286e
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xAB8 2744 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