Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ad4b5c98048fe9f…

MALICIOUS

PDF

2.2 KB
MD5: 297cedc1ef97ae53b44d7831f5badc20 SHA-1: fdb4fdcb1bd489be2f2647dccdf51a764f97d942 SHA-256: 8ad4b5c98048fe9f9ef718c4426e61dfd15c01d16589388607849ddfccf146ac
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1071.001 Web Protocols

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, PDF_EVAL, PDF_UNESCAPE, and PDF_FROMCHARCODE. The ClamAV detection 'Pdf.Exploit.Agent-36098' strongly suggests a known PDF exploit. The deobfuscated JavaScript stream, though large, likely contains code to download and execute a secondary payload, which is a common attack pattern for malicious PDFs.

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36098 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36098
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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_obj111611_000.js
e1ab3bbf30605cecdce6db9d2556198626dbb178f7a4cb471a9436bb6e8bd92f
pdf-javascript-stream PDF /JS object 111611 at offset 0x79C 462 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
59cf66d8b46f58f88380a675691962fb03d8fc94bd0795f48f5ce42e3bea4365
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2840 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).