Malicious PDF — malware analysis report

Static analysis result for SHA-256 820a055fab784d31…

MALICIOUS

PDF

40.0 KB
MD5: 7974c7285fd966df70b5b8ca6e356c83 SHA-1: ebb66c9b57e181f9165d746121c249d0f9d4643f SHA-256: 820a055fab784d312b11d9601a6588925d1e2396a8a96f1f7860e5772e7ed567
198 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript and triggers a critical heuristic for CVE-2009-4324, indicating exploitation of a known vulnerability. The deobfuscated JavaScript, named 'legacy_pdfkit_stage_000.js', likely serves to download and execute a secondary payload. ClamAV detections further confirm the malicious nature of the file and its extracted artifacts.

Heuristics 6

  • 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)
  • ClamAV: Win.Trojan.Agent-36169 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Trojan.Agent-36169
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • 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
6bd5e3e260c37e55548608f80237dc9e3181c4fb89a7403a39c794ef9aebdf90
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2019 bytes
Detection
ClamAV: Win.Trojan.Agent-36169
Obfuscation or payload: unlikely
legacy_pdfkit_stage_000.js
6615bafdfca3443f4e226384bdb5b622622cea29fad1cb3aad6a924ef5787e9e
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x9FE 2540 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