Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd0cdf9695d1d5e5…

MALICIOUS

PDF

118.7 KB
MD5: 8da37c83a4bb5cba4d9a098231384e8b SHA-1: a0305e150fd7180c981218259ca3766727a062f4 SHA-256: fd0cdf9695d1d5e53426bbbd5e217025ffdd25a8dc065aeff1d556cd901ed8a2
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, including a high-severity heuristic for a 'Large comment-padded JavaScript eval stager'. This indicates the script is designed to deobfuscate and execute further code. The ClamAV detection 'Pdf.Exploit.Agent-36086' strongly suggests this is a known exploit. The presence of JavaScript actions and eval() calls points to an attack pattern involving the execution of malicious code within the PDF.

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
69d20a11fd0e7762253fb022eb5f2d00f27167aebebba3ba7f04e1e499fac219
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627695 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
cc7440707d2a8b107c607cdd83ce8879ca7778bca5a0f4514d1554a97acaa49c
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 610 long base64-like blob(s).