Malicious PDF — malware analysis report

Static analysis result for SHA-256 5159793a609d1a2e…

MALICIOUS

PDF

40.0 KB
MD5: 2ab1ed3ad5dad347d3ea59595abd1367 SHA-1: 530a62830e00afbcb76e85bbe8afc882e270c2e0 SHA-256: 5159793a609d1a2ef040a3ec63ab0fa9cd7aa018fb22becebd14a94848b4328e
138 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF file contains embedded and obfuscated JavaScript, as indicated by the PDF_JAVASCRIPT and PDF_JS heuristics. The ClamAV detection of 'Win.Trojan.Agent-36169' on both the original file and an extracted artifact strongly suggests malicious intent. The deobfuscated JavaScript likely serves as a downloader for a second-stage payload, although the exact URL or execution method could not be fully reconstructed due to obfuscation.

Heuristics 5

  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0008_000.js
2d6074108f30c19edb3d689408a7278e346aae90da6a18d1522fa2f3c4ebe471
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).