Malicious PDF — malware analysis report

Static analysis result for SHA-256 c2f53f663f770e50…

MALICIOUS

PDF

183.3 KB
MD5: e3b5ffd121f7a74fc13285fd39d1ef0a SHA-1: 999a31b254cce334a6dd45dcbd02e6d7a524ef47 SHA-256: c2f53f663f770e50ac46579f422b6493124e67c90b558b580396261315cab56c
78 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 Command and Scripting Interpreter: PowerShell T1204.002 Malicious File Execution: Malicious JavaScript

The PDF contains embedded JavaScript, indicated by multiple heuristics including PDF_JAVASCRIPT and PDF_JS. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript file, javascript_obj0008_000.js, is highly suspicious and likely responsible for executing the malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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_obj0008_000.js
913522c4b9166798cf304d1951c8cee54982eb57eb382e9826ae1beda9d3c5b2
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 62311 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).