Malicious PDF — malware analysis report

Static analysis result for SHA-256 191070688266c38d…

MALICIOUS

PDF

31.8 KB
MD5: 59149da6bd65971f6b3ff3e33e1430a0 SHA-1: e0879e4ba534b28f0c57943b6abd23295e61b993 SHA-256: 191070688266c38dbf46bb60b874763c3baa0f4a8290343284a707ccc4cb7145
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 exploited to execute JavaScript. Heuristics indicate a stager designed to evaluate numeric expressions, a common technique for obfuscating malicious code. ClamAV detection as Js.Exploit.HTML-30 further confirms the presence of exploit code. The embedded URL, while seemingly benign, is part of the XFA structure and could potentially 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: 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/