Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfa014920c408623…

MALICIOUS

PDF

15.7 KB
MD5: 7a844604b60c9505086850f3eec3444f SHA-1: 07f6c03fda393654edf0898416b7b98d7101adca SHA-256: bfa014920c408623512d95320cf45af0486f0a6219f6d980b92719a83b94ba4c
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, which is heavily obfuscated and uses `eval()` and `String.fromCharCode()` functions. Heuristics indicate a large comment-padded JavaScript eval stager, suggesting it's designed to deobfuscate and execute malicious code. The ClamAV detection 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The primary function of the embedded JavaScript appears to be downloading and executing a second-stage payload, as indicated by the obfuscated nature and the presence of an extracted JavaScript file.

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
b2501e69cd5ce3b4ae3d66fa3305c53be76dbb788d1f035d9d567d562f204dcb
pdf-javascript-stream PDF /JS object 6 at offset 0x143 424787 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).