Malicious PDF — malware analysis report

Static analysis result for SHA-256 e285f74c3ec1ed0f…

MALICIOUS

PDF

2.5 KB
MD5: 223de175533ee8a31fb34ea11df27b67 SHA-1: 9342645715e385e1f3eba874e1f39adacb390351 SHA-256: e285f74c3ec1ed0fb428153e4d5549e64f3b556baf3c1ee0084a41a5527fcfb2
206 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1204.002 Malicious JavaScript

The PDF sample contains embedded JavaScript, flagged by multiple heuristics including PDF_JAVASCRIPT and PDF_JS. The presence of PDF_EVAL and PDF_JS_EXPLOIT_CLUSTER strongly indicates that the JavaScript is malicious and intended to exploit a vulnerability within the PDF reader. The ML classifier further confirms this with a high probability. The script's likely intent is to download and execute a second-stage payload, a common technique for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • Correlated malicious PDF JavaScript signals critical PDF_CORRELATED_MALICIOUS_JS
    PDF JavaScript or auto-action content is corroborated by exploit staging, ML, or suspicious extracted-artifact findings. This correlation promotes old exploit-kit PDFs that otherwise remain in the suspicious band because each individual signal is intentionally weighted conservatively.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (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.