Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd6b5dd7f4d6f47e…

MALICIOUS

PDF

118.5 KB
MD5: 4eda941d7b1dc7449bfbcd40d5900d20 SHA-1: 2c66b08c3662a71df839b4f07621be105c43a312 SHA-256: bd6b5dd7f4d6f47efe63ef60c7e8431295fd44f2151b8efcb4e3245befd4c33c
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, including a large comment-padded eval stager and calls to eval() and String.fromCharCode(). These heuristics, along with the ClamAV detection of 'Pdf.Exploit.Agent-36086', strongly indicate that the PDF is designed to exploit vulnerabilities and execute malicious code. The embedded JavaScript is likely responsible for downloading and executing a secondary payload, as suggested by the 'Suspicious extracted artifact' 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
047e50717d57a32bc8eb536152325fc26c7a9030a64fcac178c02fc58c9116cb
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627785 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).