Malicious PDF — malware analysis report

Static analysis result for SHA-256 8aef88d923d25a62…

MALICIOUS

PDF

10.9 KB
MD5: cd05edd0e0e20bdae7c2450347a37636 SHA-1: 3da9df06cb3cf3392d38a613e8775d24ce604780 SHA-256: 8aef88d923d25a620c3ff85c04298b7f619b2c1e96f567d88deb9eb42f9c64bc
88 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded JavaScript, indicated by the PDF_JAVASCRIPT and PDF_JS heuristics. The ML classifier strongly flags this PDF as malicious. The unescape() call suggests obfuscation within the JavaScript, which is further supported by the 'Script obfuscation indicators' signal associated with the extracted javascript_obj0007_000.js file. The likely intent of the embedded script is to download and execute a secondary payload, a common technique for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • 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_obj0007_000.js
40d2fb4312bfd5453e8d75c68c56062850ab7de5c86dada838935e031b0302f6
pdf-javascript-stream PDF /JS object 7 at offset 0x233 47867 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 244 eval/decoder/string-building token(s).