Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a90478a972e7ebd…

MALICIOUS

PDF

118.5 KB
MD5: 7df769ae5056daa62f8ae8da5bd1ee3d SHA-1: 25f5ce856bbf9e7c37a9f08a6b9139356cc6a718 SHA-256: 2a90478a972e7ebd787970afb3d6ec01f07b463a7e1f44cdc36b9cb9a89b30f6
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_EVAL. A critical ClamAV detection of 'Pdf.Exploit.Agent-36086' strongly suggests malicious intent. The presence of a large comment-padded JavaScript eval stager further supports the execution of obfuscated code. While the exact payload is not clear from the static analysis, the combination of these factors points to a malicious PDF designed to exploit vulnerabilities and execute arbitrary code.

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
71c94a18f0e88ebc9be238d2f7807d532099cbb841b26ba67ed0084d479c9d61
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627534 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).