Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c6e79871bc36a87…

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: f6c36a9f616c812aa74aaa75ba12209a SHA-1: 452a27eac9aecafdbf8e004ecd625181f1bd30eb SHA-256: 4c6e79871bc36a8764d0e2dc94cf68506eea19f6bed70c646c51f143ec34be88
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File T1566.001 Spearphishing Attachment T1566.002 Spearphishing Link

This PDF file contains embedded JavaScript, triggered by an OpenAction, which utilizes eval() and String.fromCharCode. The critical CVE-2007-5659 heuristic indicates the exploitation of a known vulnerability related to the Collab.collectEmailInfo object. The JavaScript is obfuscated and likely downloads and executes a second-stage payload. The presence of these elements strongly suggests a malicious intent, likely to deliver further malware.

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
b73251951e41f3462472c79eb0a6f4df06c859d9b3169388b73cae98f11d55b4
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 13315 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
38f5ef7c4ceb50243f5135a475f53b5a895671a924672b19a58777e7c3717b72
deobfuscated-js numeric char-code string decoded JavaScript at offset 0x445 3972 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).