Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9733076899d8ed1…

MALICIOUS

PDF

118.5 KB
MD5: bbf96b7a8223c49da5a9b4d392590dca SHA-1: 498a74fc1001035b3abdeab0472f519792961258 SHA-256: e9733076899d8ed12800cc6e7d4f65588a6d09aeca80f8e6e3bf62f349b6dcf3
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File

The PDF file contains embedded JavaScript that utilizes `eval()` and `String.fromCharCode()`, indicating an attempt to obfuscate malicious code. The presence of a 'Large comment-padded JavaScript eval stager' heuristic firing, along with ClamAV detection as 'Pdf.Exploit.Agent-36086', strongly suggests this is a malicious PDF designed to exploit vulnerabilities and download further malicious content.

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
7803f7bc3b67a3829511dfcfdac820b5b077bb1549fdfb2114fb1c88c20e1445
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627113 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).