Malicious PDF — malware analysis report

Static analysis result for SHA-256 b29999f020432f44…

MALICIOUS

PDF

92.8 KB
MD5: e0934eb79d55a3eaa077abe9a4bf16a4 SHA-1: 995389cf27eff6a90ab58ad54f7f3068707e26b4 SHA-256: b29999f020432f4406c66273f3cceeb65a08099293f695951576989449a57fd3
108 Risk Score

Malware Insights

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

The PDF document contains embedded JavaScript, flagged by multiple heuristics including PDF_JAVASCRIPT and PDF_JS. A critical heuristic identified the CVE-2009-4324 exploit targeting the media.newPlayer function, which is used to launch embedded scripts. The ML classifier strongly indicates maliciousness. The embedded JavaScript, specifically the reconstructed string "/hi av hax", suggests an attempt to download and execute a second-stage payload, although the exact URL is obfuscated. The presence of obfuscated JavaScript and the exploitation of a known PDF vulnerability point to a downloader or dropper.

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
8f34cdf022f60f656ab548204bfa7f3875947048a8aa75474445a3209ff6edf6
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2578 bytes
legacy_pdfkit_stage_000.js
ada8be7fcbbba2749cefe5122fc7e86dce72eb1b6eeddf6c5a324ca92ef02182
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xC2D 2546 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