Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f76713cd627c7aa…

MALICIOUS

PDF

118.7 KB
MD5: 5e4fc5155d0b00fa00942f88910234a1 SHA-1: cf27a105319e53e40520fb881f00fb51634d4fc4 SHA-256: 8f76713cd627c7aafc4fb5c2d0edfc07abdf96deb7367aa9fa642e3ae60bc1e6
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded JavaScript, with multiple heuristics indicating the use of eval() and fromCharCode for obfuscation and execution. The critical ClamAV detection 'Pdf.Exploit.Agent-36086' strongly suggests this is an exploit document. The embedded JavaScript stream, particularly the 'Large comment-padded JavaScript eval stager', indicates a sophisticated attempt to hide malicious code, likely to download and execute a second-stage payload.

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
0c343e9d3e7d608291e3b3d1116d9f16cda9671466a83714e5e2518dfc3d3e9d
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627107 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).