Malicious PDF — malware analysis report

Static analysis result for SHA-256 f31a46f7f3cbce2c…

MALICIOUS

PDF

118.7 KB
MD5: 7e50c38eeb1d22460370154106d81e61 SHA-1: 84a882520b30ea489dd822425af4f24a86a53f42 SHA-256: f31a46f7f3cbce2c8f39b4fef259df80d60f25be2393c16473aaebefa86faf6a
166 Risk Score

Malware Insights

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

The PDF file exhibits multiple high-severity heuristic firings related to JavaScript execution, including eval() calls and a large comment-padded JavaScript eval stager. ClamAV also detected it as 'Pdf.Exploit.Agent-36086'. The embedded JavaScript stream, which is heavily obfuscated, likely contains code to exploit a vulnerability within the PDF reader or to download and execute a secondary payload. The presence of JavaScript actions and embedded JS streams strongly suggests 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
abdfc72765bbae881d836c6aa6891b624dc3633b2869bd33017ecf38dbe3a84e
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626930 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).