Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa55629a8a6f20f7…

MALICIOUS

PDF

3.6 KB Created: 2008-31-20 53:85:00 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: 16929e865ee5019fc685800bf738c5ec SHA-1: 95b87bc16a83f2ed41c30e2e083db971dec9ed2e SHA-256: aa55629a8a6f20f7aa13f1abf450df8bc53ff7de14dc435102282b332081b83e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.002 Spearphishing Attachment

The PDF file contains embedded JavaScript triggered by an OpenAction, a common technique for exploiting PDF reader vulnerabilities. The critical CVE-2007-5659 heuristic indicates the use of a specific exploit targeting the `Collab.collectEmailInfo` method, which is used to decode and evaluate obfuscated JavaScript. This script likely downloads and executes a second-stage payload, as suggested by the presence of deobfuscated JavaScript streams and suspicious extracted artifacts. The confidence is high due to the specific CVE firing and the presence of executable script content.

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
66e57e6ec6a284531962e5226a316d9b51f03f4964c4bb293e6f14e46d78c806
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 14011 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
8607f50aef0173a3002ae209b7d2562c522cb686a9c767ca711e8df4ec727008
deobfuscated-js numeric char-code string decoded JavaScript at offset 0x445 4260 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).