Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6cc8506989a0530…

MALICIOUS

PDF

25.8 KB
MD5: ae3cd89272b1f6da0cd23e1b4e3be195 SHA-1: af8d7c93a3d10489722761bfb81b87cb4cf0cc88 SHA-256: b6cc8506989a05308eb4cf9b1c37032ccc76fe15946ab7263285f1026bd48595
156 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript, indicated by PDF_EMBEDDED_SCRIPT_PAYLOAD and PDF_XFA_SCRIPT heuristics. The script utilizes unescape() and String.fromCharCode, suggesting obfuscation to hide malicious code. The ML classifier strongly flags this PDF as malicious. The embedded file artifact further supports the likelihood of a multi-stage attack. The primary intent appears to be the execution of this script to download and run a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 8

  • 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.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits
  • Embedded script payload in PDF stream medium 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 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
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • 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/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
1752285fa6768e44cd827da48a217425761e78747457b670d2b7ba1d55792c93		 pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC6 25746 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).

Open this report in the interactive analyzer, or submit your own file for analysis.