Malicious PDF — malware analysis report

Static analysis result for SHA-256 71cf3aa1bca1f992…

MALICIOUS

PDF

9.6 KB
MD5: 2b8a88af753dae7e40a4274b3c9c5aff SHA-1: b188c367bf0dbe2dbc86298e1e1f279127a0e0b3 SHA-256: 71cf3aa1bca1f992d79f6fea73b6f8bc0e89199b47e17caea2603d1fb9ad49cd
118 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains XFA form elements and triggers a critical heuristic for CVE-2010-0188, indicating an exploit for Adobe Reader. The extracted JavaScript, specifically 'xfa_base26_stage_000.js', appears to be part of the exploit chain, likely responsible for downloading and executing a secondary payload. The ML classifier strongly flags this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • 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
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • 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-locale-set/2.1/
    • http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/1.0/
    • http://www.xfa.org/schema/xfa-template/2.2/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0041.bin
c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
pdf-embedded-file PDF EmbeddedFile object 41 at offset 0x109C 85 bytes
embedded_file_obj0042.bin
dda0835df994b8be920f715db36452f6cee7bb42bbc9c897f878a7b298ba8e91
pdf-embedded-file PDF EmbeddedFile object 42 at offset 0x114E 1029 bytes
embedded_file_obj0063.bin
d16884459d6f5ff8bb14cd963783e6b1299a8a83cb490d0d36447c8ec2b3e4de
pdf-embedded-file PDF EmbeddedFile object 63 at offset 0x1367 8284 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
embedded_file_obj0044.bin
3dd68f00f4fcb366a2a3a17c65cb2626eeddf5ea5713302d374310561d810169
pdf-embedded-file PDF EmbeddedFile object 44 at offset 0x233F 144 bytes
embedded_file_obj0045.bin
10c03f88a5f0a0833dc5b2c8ac295b3a3c6f65e23889eb8cc1dc6fe29bf7f275
pdf-embedded-file PDF EmbeddedFile object 45 at offset 0x23EC 77 bytes
xfa_base26_stage_000.js
d8d3ec5f47d325a68c42d6909eb045895d79b4aacc4c4f8180318a569d1f0119
deobfuscated-js XFA base-26 decoded JavaScript (decompressed) at offset 0x17B6 2146 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s). Carved artifact contains 3 long base64-like blob(s).
deobfuscated.js
92da60de85d033c6eabc9dea03006930665abf2e9f343dc35727606d3ba939fc
deobfuscated-js PDF JavaScript deobfuscation pass 20756 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).