Pdf.Dropper.Agent-1858657 — PDF malware analysis

Static analysis result for SHA-256 ba3c7c763f7910ef…

MALICIOUS

PDF

24.6 KB Created: 2010-09-10 02:11:18 Authoring application: Scribus 1.3.3.14 (via Scribus PDF Library 1.3.3.14)
MD5: 659cf4c6baa87b082227540047538c2a SHA-1: a93bf00077e761152d4ff8a695c423d14c9a66c9 SHA-256: ba3c7c763f7910ef956e27be054e9271b00d05aab9fb153cdf30001ce422d68a
274 Risk Score

Malware Insights

Pdf.Dropper.Agent-1858657 · confidence 95%

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file contains embedded JavaScript and is flagged by multiple heuristics, including a critical PDF JavaScript exploit cluster and ML classification, indicating malicious intent. ClamAV identifies it as Pdf.Dropper.Agent-1858657. The presence of an embedded file and a secondary embedded PDF suggests it acts as a dropper for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 12

  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • Secondary embedded PDF body has suspicious static findings critical POLYGLOT_CHILD_PDF_STATIC_TRIAGE
    A valid PDF body was found at a nonzero offset inside another container and its carved contents matched PDF exploit or lure heuristics. This catches polyglots where the top-level magic routes to ZIP/OLE while a PDF reader or downstream parser opens the hidden PDF payload.
  • ClamAV: Pdf.Dropper.Agent-1858657 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-1858657
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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
  • ASCII85Decode filter (with exploit indicators) low PDF_FILTER_85
    ASCII85 encoding filter present alongside exploit delivery indicators — uncommon outside of obfuscation
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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/xci/1.0/
    • http://www.xfa.org/schema/xfa-template/2.4/
    • http://www.xfa.org/schema/xfa-data/1.0/
    • http://ns.adobe.com/xtd/
    • http://www.xfa.org/schema/xfa-form/2.8/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0021.bin
0309db5850dea096d566c8ed55dab6d656854b8b97c501a4ba94a0df94dbb272
pdf-embedded-file PDF EmbeddedFile object 21 at offset 0x5874 13430 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
polyglot_child_pdf_off00000001.pdf
43f51ae5b02a74c88eb1a1221f8a4bc1b30f5363523a6588c1ae0f16d97c152f
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x1 25168 bytes