Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7f6c509d633d2e4…

MALICIOUS

PDF

118.6 KB
MD5: 04de180c2f9ef9e2f24754fc61502905 SHA-1: caadb59c7394d80e6049bd625f71a260603f1672 SHA-256: a7f6c509d633d2e49a0563893090e9bcb5a54f083545520b0f4b1475ec3076cb
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link T1566.002 Spearphishing Attachment

The PDF contains embedded JavaScript, including a high-severity 'eval()' call and a 'Large comment-padded JavaScript eval stager'. This indicates the script is designed to obfuscate malicious code execution. The ClamAV detection 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The JavaScript likely acts as a downloader for a second-stage payload, a common technique for initial access and further compromise.

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
76c1fecfe24e45000e517e39b9454ccb5d53cb0e20ec07515efcfc891262db53
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627497 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).