Malicious PDF — malware analysis report

Static analysis result for SHA-256 775d0d7c5cbb3dd0…

MALICIOUS

PDF

34.3 KB
MD5: c554d10e8a8eb47306d19e71e588d22d SHA-1: 3e194effbef5cf3f452e7be601979f9d58d859a1 SHA-256: 775d0d7c5cbb3dd0edc7d8d4d5f5b99a74ddf025e7536e01420753183d146f2f
180 Risk Score

Malware Insights

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

The PDF file contains XFA (XML Forms Architecture) which is known to be used for embedding executable scripts. Heuristics indicate the presence of risky executable scripts and a numeric evaluation stager, strongly suggesting an exploit. The ML classifier and ClamAV detection confirm its malicious nature, likely as a dropper for further malware. The embedded URL, though seemingly benign, is part of the XFA structure and could be used in conjunction with the exploit.

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: Pdf.Exploit.Dropped-92 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-92
  • 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/