Malicious PDF — malware analysis report

Static analysis result for SHA-256 a000d90f396617bb…

MALICIOUS

PDF

24.4 KB
MD5: b9288e027426223bb79cf668a7115ed7 SHA-1: d1edefd851004809e222916634dbb4e801ceb780 SHA-256: a000d90f396617bbfba2c1f19b148dcef38f527e5024ba525e2774e31ab37897
156 Risk Score

Malware Insights

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

This PDF sample was flagged as malicious by an ML classifier with high confidence. High-severity heuristics indicate the presence of risky executable script within an XFA form, and an embedded file was detected. The script likely attempts to download and execute a second-stage payload, as suggested by the 'unescape()' and 'String.fromCharCode()' firings, which are common obfuscation techniques used to hide malicious code. The embedded file 'embedded_file_obj0008.bin' is also a strong indicator of a dropper or downloader.

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
c0abf0729ea06c30bac2db98fced0c0bb8aa31eb4915952aa5f907d9121eb343
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC6 24274 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).