Malicious PDF — malware analysis report

Static analysis result for SHA-256 b116a61b1f70fae6…

MALICIOUS

PDF

118.6 KB
MD5: e11e28cafb43923145f5b0df87eb19cd SHA-1: 01e3e4aa8e6424c6426a6af4121541ece6c2b4fd SHA-256: b116a61b1f70fae672facb684d1544b23f8510e42471e576cafab053a124978b
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1566.002 Spearphishing Attachment

The PDF contains embedded JavaScript, including a large comment-padded eval stager, which is a common technique for obfuscating malicious code. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary attack pattern involves leveraging JavaScript to execute arbitrary code, likely for downloading and running a secondary payload. The specific ClamAV detection name 'Pdf.Exploit.Agent-36086' is included as a key indicator.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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
33306d2f70e940a7341ef3b251fa6c1aa84adda4160ce68234f101a27bfd8695
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627230 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).