Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fe71e0dc7542a3c…

MALICIOUS

PDF

118.7 KB
MD5: 58193a72dafcd1a857a102f2145eb31b SHA-1: 3f9f6f44a8207e7895f20f9e755cf24c47f55290 SHA-256: 9fe71e0dc7542a3c47656d889e52280748fa2db74b59ccd9b6135fa22ded7492
166 Risk Score

Malware Insights

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

The PDF file contains multiple JavaScript streams, including one with a large comment-padded eval stager. ClamAV detected this as 'Pdf.Exploit.Agent-36086', indicating a known exploit. The presence of eval() and String.fromCharCode() suggests obfuscation and dynamic code execution, typical for PDF exploits that aim to download and run 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
3fe8738e9a3b3a05f2c62b6ac8421a113a021912d1215ecb7dbef7ece572a1e6
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626943 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).