Malicious PDF — malware analysis report

Static analysis result for SHA-256 f59c948fd76b3289…

MALICIOUS

PDF

118.5 KB
MD5: 2b4137846d24358d9160142adbc4d32b SHA-1: 44a6633f55bb3a25a3df390d9fa9c62f4154c4d6 SHA-256: f59c948fd76b3289fe9a19d80b13faabe13793064d3101d151a7d8db6b538325
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1059.007 JavaScript

The PDF contains embedded JavaScript with multiple high-severity heuristic firings, including `PDF_EVAL` and `PDF_JS_LARGE_COMMENT_PADDED_EVAL`. These indicate the use of obfuscated JavaScript for executing malicious code. The `CLAMAV_DETECTION` heuristic further confirms its malicious nature, identifying it as `Pdf.Exploit.Agent-36086`. The primary attack vector appears to be JavaScript execution within the PDF, likely leading to exploitation.

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
0d4cbd3c704cbc0bb8cb9cbd92437968e48107f7249e1b353ce582869968d584
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627131 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).