Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9aca872852fbdc1…

MALICIOUS

PDF

118.5 KB
MD5: 68952611914b1ef586afc1ac20720375 SHA-1: 2fb6b839769bafd1e2f5b1eff3e0d0d1e42f9601 SHA-256: e9aca872852fbdc1493d2ef7f499624c68b1f157095acd951135e0359bd554af
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1059.007 JavaScript

The PDF file exhibits multiple high-severity heuristic firings related to JavaScript execution, including the use of eval() and a large comment-padded eval stager. ClamAV also detected this file as 'Pdf.Exploit.Agent-36086'. The embedded JavaScript stream, though obfuscated, strongly suggests an attempt to exploit PDF vulnerabilities to download and execute further malicious content. The presence of `eval()` and `String.fromCharCode` within the JavaScript stream indicates a deliberate effort to obfuscate malicious code, likely for payload delivery.

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
ad7aa9f3c02aef73e04a8cf493ae13d4c6aedaa0d8554f3a50a5156d4e42e09e
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626894 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).