Malicious PDF — malware analysis report

Static analysis result for SHA-256 8deb4ae463268da4…

MALICIOUS

PDF

118.6 KB
MD5: 67471d0d79d49902d4de72ccafb9a6e2 SHA-1: 80f1315997b13cd8bd0543e6ad5f336ea18fc79f SHA-256: 8deb4ae463268da4872165a177a57ded65ec19898d2b858d26de89278fe6c249
166 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', 'PDF_JS', and 'PDF_EVAL'. A critical heuristic 'CLAMAV_DETECTION' identified the file as 'Pdf.Exploit.Agent-36086'. The presence of 'eval()' and 'String.fromCharCode' within the JavaScript stream suggests obfuscation and dynamic code execution, typical for downloading and executing further malicious content. The large comment-padded JavaScript eval stager further supports this. The primary attack pattern involves exploiting PDF vulnerabilities to run this script.

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
c81f58d57e3b8e96ca72904b7182e63c9d0461c657980d03763f7ee3dcc00c72
pdf-javascript-stream PDF /JS object 6 at offset 0x143 628035 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).