Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4c65728b8fbc5f8…

MALICIOUS

PDF

3.5 KB Created: 2008-31-20 53:85:00 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: fcd2d6994ba99a27e693b668440b96f8 SHA-1: ab6c1ba5ab28b8647015301b266639580fad6082 SHA-256: b4c65728b8fbc5f8bbd8ae97bc3f4e5ee4c34ecdc49a3456da44eac750cdfe86
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains embedded JavaScript that is triggered by the OpenAction. Heuristics indicate the use of eval() and String.fromCharCode, suggesting obfuscated code execution. The critical CVE-2007-5659 firing points to the use of Collab.collectEmailInfo to achieve code execution. The embedded JavaScript is likely responsible for downloading and executing a second-stage payload, although the specific URL or payload could not be reconstructed from the provided evidence.

Heuristics 7

  • 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. (identified after JavaScript deobfuscation)
  • OpenAction trigger high PDF_OPENACTION
    PDF has an /OpenAction — code runs automatically when opened
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (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.
  • 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)
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_001.js
5701550055a1f785854e00daadfff1f70dbbe0dde0f1943bb66c1e0e543e1cff
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 13505 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
numeric_charcode_stage_000.js
c40de0a5c294c55664dd82b42602ea92f38fc8cbb8f0467cbcc23b78f2f11720
deobfuscated-js numeric char-code string decoded JavaScript at offset 0x445 4032 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).