Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec73bab4ea12323b…

MALICIOUS

PDF

15.7 KB
MD5: 5b8e8ea3a0a3c6a750ba4c6e786db77d SHA-1: 69090b4178cb03dab274f1e31df8a735b6e9506f SHA-256: ec73bab4ea12323be1694f12382cb3da484d0f9785148b26ac48a7caa4e67c6a
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, including a high-severity 'eval()' call and a 'Large comment-padded JavaScript eval stager'. ClamAV identifies this as 'Pdf.Exploit.Agent-36086'. The presence of JavaScript and the specific heuristic firings strongly indicate that the script is designed to exploit a vulnerability within the PDF reader to download and execute a secondary payload. The exact nature of the payload cannot be determined from the provided evidence.

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
c501060217f6c958d04e807cdb67f9502b0259b9e2f8f3d3fb5fcb7393dd400c
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425559 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).