Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6e83748e916e32e…

MALICIOUS

PDF

67.8 KB Created: 2008-02-27 16:58:09 +08:00 Authoring application: PScript5.dll Version 5.2 (via Acrobat Distiller 6.0.1 (Windows))
MD5: e7c130453c996946814b02153db46551 SHA-1: e4b5fb86edade0ff8facf1dea6f082260f4e78d4 SHA-256: b6e83748e916e32e4b690915c03abefe84a5da4e89f472ee547c320267cadae1
228 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File

This PDF file contains embedded JavaScript that utilizes the unescape() function and exploits CVE-2007-5659 (Collab.collectEmailInfo). The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function of the embedded script appears to be downloading and executing a second-stage payload, as suggested by the 'Win.Trojan.Dropper-82' ClamAV detection and the 'Suspicious extracted artifact' heuristic. The document body is heavily obfuscated and does not provide clear user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 10

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (matched in decompressed stream)
  • ClamAV: Win.Trojan.Dropper-82 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Trojan.Dropper-82
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PermissionError. 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://www.w3.org/1999/xhtml
    • http://www.xfa.org/schema/xfa-data/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/iX/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0017_000.js
a855e1484b6aa802ce0f6f936ba6d5b5bb5556ec34d1f510cb7f17c768fa4311		 pdf-javascript-stream PDF /JS object 17 at offset 0x6A2 4622 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 16 eval/decoder/string-building token(s).

Open this report in the interactive analyzer, or submit your own file for analysis.