Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e530aaeee3c6137…

MALICIOUS

PDF

15.7 KB
MD5: 69d61d1103556b702cdacb451d3196d8 SHA-1: e0a3d35535fe3811123cf2ce8fafe41fd0b0f7d9 SHA-256: 9e530aaeee3c6137d01587dab9116de1d7b4d581d074f80b9f7016dcd5abfe5f
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_EVAL'. The 'PDF_JS_LARGE_COMMENT_PADDED_EVAL' heuristic suggests a stager designed to execute obfuscated JavaScript. ClamAV detection 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The embedded JavaScript streams, particularly 'javascript_obj0006_000.js' and 'legacy_pdfkit_stage_000.js', are likely responsible for exploiting a vulnerability and initiating a download or execution chain.

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
fa39546b59f1691106205b47fb13c82167257fb669ea65e71ba181edbbc743f0
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425156 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
6141856231e8277b1d9f844529f9a8c5cabc30854c302d22c513a6506581aefe
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 564 long base64-like blob(s).