Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cd189b9d2c76b55…

MALICIOUS

PDF

118.6 KB
MD5: b27512f1a95a42ecf6b34754d5fab781 SHA-1: 82f0929f4c5e55c76b915a5db4544d24afa8c851 SHA-256: 8cd189b9d2c76b5584a7bacf2244ba84f85c60fd7bca68d933ec619fdfe29c28
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF contains embedded JavaScript, including a heavily obfuscated 'eval' stager. This stager is designed to decode and execute arbitrary code, a common technique for downloading and running further malicious payloads. The ClamAV detection 'Pdf.Exploit.Agent-36086' strongly indicates malicious exploit activity within the PDF.

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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
3d591475b16ef4d24cad09fd4ec3300d00708b63a7190932d21cc259a99f470c
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627555 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).
legacy_pdfkit_stage_000.js
490b230c3a6728e1ac8310d761fa086ad161b0edf86b30db54827ed4d2fb33c2
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 629 long base64-like blob(s).