Malicious PDF — malware analysis report

Static analysis result for SHA-256 f2a792dcecc85fcd…

MALICIOUS

PDF

118.5 KB
MD5: 9cb0fcae53203b4fcdf640e83c8a4160 SHA-1: f772953e90a3eb1b5f9d59d3970d0585313f679e SHA-256: f2a792dcecc85fcdaa9fd531ecb8d0557cf35ac0e2be06f145677dab6ff931ad
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, indicating it's designed to execute malicious code. The presence of `eval()` and `String.fromCharCode` functions strongly suggests code obfuscation and execution. ClamAV detection as 'Pdf.Exploit.Agent-36086' further confirms its malicious nature, pointing towards an exploit attempt.

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
619a4f918968180fa48d2b9a4dfd2eeb39bb58b414e36df6e0ad7ebdd566e790
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626580 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
819e21251ded202da855445d52a65b3d9886ab52c54a87f8afb62598167ea4c7
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 574 long base64-like blob(s).