Malicious PDF — malware analysis report

Static analysis result for SHA-256 49a93f8ad87ff4fa…

MALICIOUS

PDF

15.7 KB
MD5: 9aaf2568339442c401cffdd055eb38ef SHA-1: 98bd488883ed5db6521c0d882f7786c9ba25a8f3 SHA-256: 49a93f8ad87ff4fa6fbfcdc0df0128c91f99161dfca3f10c8e178243a3ccadf8
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1071.001 Web Protocols

The file is a PDF containing embedded JavaScript, as indicated by multiple PDF_JAVASCRIPT and PDF_JS heuristics. The JavaScript stream includes an eval() call and a large comment-padded eval stager, suggesting an attempt to obfuscate malicious code. ClamAV detection as 'Pdf.Exploit.Agent-36086' strongly suggests this is a known exploit. The primary attack pattern involves leveraging a PDF vulnerability to execute this script, likely to download and execute a secondary 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
b6d8a30fd4bbb25bcf8d732f7b1df41b04c25606a2529a20b98030f7d7146ed1
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425311 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).