Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8d5dd64f731f175…

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: 7368c8610c7fa28c403649acac2a4f27 SHA-1: 5eb506df29aa1b80a14ff232fbf3faae6800a477 SHA-256: b8d5dd64f731f1758bc82d5a57bf2fb840c1b2f4bfac233a9ae059c2036fe3bd
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Shell Scripting: JavaScript T1204.001 Malicious Link: Malicious Link T1059.003 Command and Scripting Interpreter: Windows Command Shell

The PDF file contains embedded JavaScript that is triggered by the OpenAction. The critical CVE-2007-5659 heuristic indicates that the script uses a technique involving `Collab.collectEmailInfo` and character code decoding to evaluate a string, likely to exploit a vulnerability. This script is designed to download and execute a second-stage payload. The obfuscated nature of the script and the use of `eval()` suggest a malicious intent to compromise the user's system.

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
4aced3ec176c59bdcc91169335cf3d39b3fc277e0259cc5b0b35301afb5fd3db
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 13327 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
3eccd33acfa0f9aa1657e6afd8add6d2d822873e2fa089a82d80516b78931985
deobfuscated-js numeric char-code string decoded JavaScript at offset 0x445 4044 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).