Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d0d98d0c340cc78…

MALICIOUS

PDF

118.6 KB
MD5: e5c68fb4e125151fd038382f41ffea79 SHA-1: c44087f6062960a5f5c053d7a858d87f03b50abc SHA-256: 8d0d98d0c340cc78d59db418ce460f3c6c758ddbb23d431d547b9cdf382214af
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_EVAL'. The 'PDF_JS_LARGE_COMMENT_PADDED_EVAL' firing suggests a stager designed to obfuscate malicious code. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary attack pattern involves leveraging JavaScript to execute arbitrary code, likely to download and run a secondary payload, as suggested by the presence of an embedded JavaScript file.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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
1e8b9df213a9dd4521dbbd65556f7abe43a4923e94708d23571afaf4e3090e32
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627168 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).