Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5ef850b81e88e26…

MALICIOUS

PDF

32.6 KB
MD5: 289d80af18448d7292b854ae522a5eb9 SHA-1: 34faa0b43f9b0ee34ff0129198fc499b9a3b95a0 SHA-256: e5ef850b81e88e26727bd06cfd973b09b0a5724996145c8ccf6a1d67a738dac3
178 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains an XFA form with executable JavaScript, identified by multiple high-severity heuristics. The script appears to be a stager designed to evaluate numeric expressions and construct a string, likely to download and execute a second-stage payload. The ClamAV detection 'Js.Exploit.HTML-30' further confirms its malicious nature. The embedded URL is likely part of the exploit chain.

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/