Malicious PDF — malware analysis report

Static analysis result for SHA-256 be4639a230d2bfd9…

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: d8480f1d6ef26ee4ef6b1e25d616d7a8 SHA-1: 91c78db89ac0a550dff18b9c68290769471d9d87 SHA-256: be4639a230d2bfd94b00de85d80a3bf1673732c34bc93c8d309c06d44e6481cd
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript triggered by the OpenAction, which is a common technique for exploiting PDF reader vulnerabilities. The critical CVE-2007-5659 heuristic indicates the use of Collab.collectEmailInfo with a numeric character-code string decoded JavaScript, which is then evaluated. This suggests the script is designed to download and execute a second-stage payload. No specific family could be identified, but the attack pattern is consistent with a malicious document dropper.

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
70b57e02334c247bac2c6f3b0b9373b37f8f3549be695e304cd2bd1cec4b6dd7
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
8153b9f160ebc630ca3b5ace2deb0cd33d3d498454c39d2d2294d86719312956
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).