Malicious PDF — malware analysis report

Static analysis result for SHA-256 05d3c5f961ff2db6…

MALICIOUS

PDF

24.5 KB
MD5: 79cfd3b9874455e84388c731d688e1dd SHA-1: ca2ebe8ed66e6d10390fbccafdb17718d2e055b0 SHA-256: 05d3c5f961ff2db6117e60bf78a8aec06198e16abc3ddac2f7426949e48025f8
180 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The file is a PDF containing an XFA form with executable script, identified as a stager by heuristics. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URL, while seemingly benign, is part of the XFA structure and likely used in conjunction with the script to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • XFA form contains risky executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose script block contains exploit, submission/launch, or shell-execution primitives. Ordinary LiveCycle print/update scripts are left as generic XFA/JS signals unless stronger behavior is present.
  • ClamAV: Js.Exploit.HTML-30 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-30
  • XFA numeric character-table eval stager high PDF_XFA_NUMERIC_EVAL_STAGER
    PDF XFA initialize script reads numeric form data from rawValue, maps the values through a short character table, and evals the reconstructed stage. This is an exploit-kit staging technique even when the final decoded layer remains encoded.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.xfa.org/schema/xfa-template/2.5/