Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae0fe3e33ba1d316…

MALICIOUS

PDF

118.7 KB
MD5: 8e5928942806a61f311fe3aef06bcc24 SHA-1: 28d15583117b368b720d198d0ab4b369137cab1a SHA-256: ae0fe3e33ba1d316763478eaa84042400005ede41c800218a02d44ae63969b54
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, including a large comment-padded eval stager, indicating an attempt to execute obfuscated code. The presence of `eval()` and `String.fromCharCode` further suggests code execution. ClamAV detection as 'Pdf.Exploit.Agent-36086' confirms its malicious nature. The primary attack pattern involves leveraging JavaScript within the PDF to download and execute 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
20dcb7df56b166d9ed3138451154b3490731729a76afe4ed1d1f1d49d17df326
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626847 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
fff819d60ccb4b976edca15ae7b9f3d57318022dbbbbd9ef583980a48f4e76e3
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262116 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 562 long base64-like blob(s).