Malicious PDF — malware analysis report

Static analysis result for SHA-256 fca911789f63f89d…

MALICIOUS

PDF

118.6 KB
MD5: f09f4586e826cfd1ea26c4832175f368 SHA-1: ede2a71c1284e1facfd16e1a087bff6f9b319bd6 SHA-256: fca911789f63f89d4cb875ece1a091d125ee29668ea78da1d26c2b198bbb5295
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded JavaScript, flagged by multiple heuristics including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_JS_LARGE_COMMENT_PADDED_EVAL'. The 'PDF_EVAL' heuristic indicates the use of eval(), a common technique for obfuscating malicious code. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript, named 'javascript_obj0006_000.js', is likely responsible for downloading and executing a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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
2d840afc0e680f8a047ee0f0c9450fb9b17d7ede699353d04545b25e73dea356
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627480 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).