Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ceec771de1ccae1…

MALICIOUS

PDF

15.7 KB
MD5: 051ff54643de8df708531edc1da7de67 SHA-1: ad5e6bbb7d13d753bbce4aca726b6a031253f713 SHA-256: 3ceec771de1ccae1b70d1c63b5b83041e102e7bfdaf283bd5775150e2570a289
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript with multiple high-severity heuristic firings, including 'PDF_EVAL' and 'PDF_JS_LARGE_COMMENT_PADDED_EVAL'. This indicates the script is designed to obfuscate and execute malicious code. The presence of 'Pdf.Exploit.Agent-36086' from ClamAV further confirms its exploit nature. The primary intent appears to be downloading and executing a second-stage payload, as suggested by the exploit stager heuristic.

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
35042773061e2c167704a12635bf5fb309c712b384b1b0f1e7746e2a63df6f1d
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425238 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).