Malicious PDF — malware analysis report

Static analysis result for SHA-256 421334f6b14c57eb…

MALICIOUS

PDF

21.4 KB
MD5: ac45b9e544bef58514d443f3e0cbf2db SHA-1: 8ed0bfed1c28a880f66748bcfd69aa034e122be0 SHA-256: 421334f6b14c57eb49da0de9262bbb7c03a89d6c0d006a3a625cd249c1106c11
78 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The critical CVE_2009_4324 heuristic specifically points to the exploitation of a vulnerability related to media.newPlayer via annotation actions. The embedded JavaScript, particularly the deobfuscated legacy_pdfkit_stage_000.js, is designed to leverage this vulnerability. The script's intent is to download and execute a second-stage payload, as suggested by the obfuscation indicators and the nature of the exploit.

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
c8462fe3e860a249dc237e01c7794221220e16519ab84b34a13834dccd6c0055
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2221 bytes
legacy_pdfkit_stage_000.js
c3df0b6d669953258363ab802ac0d32c63d5685d76eb2e0ad1f70f86b924f691
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xAC8 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