Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d7c6ffa735ca247…

MALICIOUS

PDF

118.6 KB
MD5: 969ff3b57fdd7d9f2549d38d0851d200 SHA-1: 6dac4725b5f872ef405950d6bb01de45c2632c45 SHA-256: 9d7c6ffa735ca2470460224773afb17223e1ebe63ceaecfa4a87eab7c875b533
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, with multiple heuristics indicating obfuscated code and eval() calls. Specifically, a 'Large comment-padded JavaScript eval stager' heuristic fired, suggesting the script is designed to deobfuscate and execute further malicious code. The ClamAV detection 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The primary function appears to be downloading and executing a second-stage payload, though the exact URL or mechanism is not directly extractable from the provided evidence.

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
f367ab681698975a9199adf490926065d00b599adcc55d683c237e276e800e7d
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627081 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
bab244ce36278ee329b34cc23024acf6a868d0ddaf880bc2ad0319c419603887
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 595 long base64-like blob(s).