Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cd5b4e87600cb45…

MALICIOUS

PDF

24.7 KB
MD5: ab04d5137b51308aba4ed26ce3c1b881 SHA-1: fd55776d6f4c8cecf4be0a8a819220ca5dcd930d SHA-256: 1cd5b4e87600cb451e7357ac61b985daae620b48693d72a2ad9e9bc241358796
230 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution: Malicious Script T1059.001 Command and Scripting Interpreter: JavaScript

This PDF file exploits CVE-2010-0188 via XFA form elements containing numeric JavaScript. The embedded JavaScript stager, recovered as xfa_numeric_stage_000.js, is detected by ClamAV as Js.Exploit.HTML-30 and likely downloads and executes a second-stage payload. The embedded URL is likely related to the XFA schema but may also be used in the attack chain.

Heuristics 7

  • Adobe Reader LibTIFF XFA image exploit — CVE-2010-0188 critical CVE likely CVE_2010_0188
    PDF contains the CVE-2010-0188 exploit template: XFA JavaScript heap-spray setup, a generated TIFF image payload, and assignment of that TIFF data to an XFA image field rawValue to trigger Adobe Reader's LibTIFF parser.
  • ClamAV: Js.Exploit.HTML-30 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-30
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • XFA numeric JavaScript stager high PDF_XFA_NUMERIC_JS_STAGER
    PDF XFA script reconstructs a hidden JavaScript stage from numeric field data or a character table, then evals the result. The decoder is gated on XFA script, numeric staging, and recovered exploit-like JavaScript or shellcode markers.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • 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://www.xfa.org/schema/xfa-template/2.5/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xfa_numeric_stage_000.js
860b46b9d5d61020e84f218356e7cd0ddccff6caafabfc72c3b0a2e88b80a6f9
deobfuscated-js XFA rawValue numeric decoded JavaScript (raw) at offset 0x3A8 3819 bytes
Detection
ClamAV: Pdf.Exploit.Agent-36962
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s). Carved artifact contains 3 long base64-like blob(s).