Malicious PDF — malware analysis report

Static analysis result for SHA-256 5299b76f26ae8ee5…

MALICIOUS

PDF

22.7 KB Authoring application: 104-85-68-126-139-88-72-90-126-104-84-74-92-114-147-145-136-141-134-77-133-145-142-140-98-135-128-145-98-142-131-132-71-126-104-86-125-126-104-87-72-90-156-145-132-147-148-145-141-63-126-104-84-156-13 (via -156-132-139-146-132-154-126-137-84-92-70-138-97-74-96-114-137-136-112-135-100-143-88-133-142-97-106-78-78-78-78-78-150-96-96-96-96-97-96-96-96-96-96-96-96-96-96-96-96-96-112-96-96-96-96-96-96-96-96-1)
MD5: ca9abbe2dc4d6ce4102935be3e9388b6 SHA-1: c969a5bc7305d644c4da73ec9168bf3b29b369d0 SHA-256: 5299b76f26ae8ee5ca36663b9e2254d7339055985434f835d6d05fd1b4d7cbfe
184 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious File T1059 Command and Scripting Interpreter

This PDF file was flagged as malicious by multiple engines, including ClamAV, and exhibits characteristics of an exploit. The presence of XFA forms with executable scripts, along with embedded files, strongly suggests it's designed to deliver a secondary payload. The ML classifier output of 0.999394 further supports a high likelihood of malicious intent. The embedded file 'embedded_file_obj0043.bin' is likely the delivered payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 9

  • 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.
  • ClamAV: Pdf.Exploit.Agent-36962 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36962
  • 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. (matched inside decoded stream)
  • 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.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0041.bin
c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
pdf-embedded-file PDF EmbeddedFile object 41 at offset 0x373B 85 bytes
embedded_file_obj0042.bin
b40a217a8d9b8d3671cc3874c550d30941b93ca6dde99995d43921dede579865
pdf-embedded-file PDF EmbeddedFile object 42 at offset 0x37ED 1183 bytes
embedded_file_obj0043.bin
abf64c787afd55dd1c99ba75b19d779fa14c2bb4eb682d88cd4080fc5ea1fa57
pdf-embedded-file PDF EmbeddedFile object 43 at offset 0x3A3D 1917 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
embedded_file_obj0044.bin
3dd68f00f4fcb366a2a3a17c65cb2626eeddf5ea5713302d374310561d810169
pdf-embedded-file PDF EmbeddedFile object 44 at offset 0x3E34 144 bytes
embedded_file_obj0045.bin
ce4a3f07835c725838e55947d6b1f21771e0ad8084ee86d0890ecc12bd5231fd
pdf-embedded-file PDF EmbeddedFile object 45 at offset 0x3EF6 2427 bytes
font_00_cff_off000042c6.bin
062eede2d0cc5d3972869dc7e2f2f9f01d1d1b3756b715c8252f06948ce99ae2
pdf-font-stream PDF embedded font (cff) at offset 0x42C6 1192 bytes