Malicious PDF — malware analysis report

Static analysis result for SHA-256 79a0c711ed917bcd…

MALICIOUS

PDF

25.0 KB
MD5: 2c76aebd746d292eadf1f468ffaa23fd SHA-1: 25e6ff2e06f6732ca8bdc5d8ac3cd12bc946c632 SHA-256: 79a0c711ed917bcd0a195a7b90bac616eaf0a2a32c4b3ba4f08e4ed72889eba3
116 Risk Score

Malware Insights

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

The sample is a PDF file flagged as malicious by ClamAV and an ML classifier. It contains embedded JavaScript within an XFA form, a common technique for exploiting PDF vulnerabilities. The script attempts to download and execute a second-stage payload, indicated by the 'ML_NYX_PDF_MALICIOUS' and 'PDF_EMBEDDED_SCRIPT_PAYLOAD' heuristics. The benign URLs are likely unrelated to the malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 5

  • ClamAV: Pdf.Malware.Agent-7872242-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Malware.Agent-7872242-0
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • Embedded script payload in PDF stream low PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • 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://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xfa-template/2.5/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_pdf_script_00000303.bin
441ef8500fc2f011ab74c6bbb1e75e3c67d3069973605b8618d74d4ccd15bb16
pdf-embedded-script PDF decompressed stream script payload at offset 0x303 25594 bytes