Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7d24ea5de800d4a…

MALICIOUS

PDF

118.6 KB
MD5: 74d78d072807ca0339a0509a6bc9508a SHA-1: 5d661ff8e2bfd82494879b01dca8a33bce28c0ff SHA-256: a7d24ea5de800d4a26782bd32b5d7ef9f168bbb69690dd3b38dc4db0b789e3ba
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File

The PDF contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_EVAL'. A specific heuristic 'PDF_JS_LARGE_COMMENT_PADDED_EVAL' suggests a stager pattern. ClamAV also identified the file as 'Pdf.Exploit.Agent-36086'. The presence of a large JavaScript stream ('javascript_obj0006_000.js') strongly suggests the script is responsible for downloading and executing a second-stage payload.

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
651b9c29c58dc15e6b65b0393d8d0384dfc1aaf9cfc59173d842aa33bb001b95
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626746 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).