Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1da6544fdf78420…

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: 01a64122684d8fc52ef308e3413f082d SHA-1: f21529927b6dae7b0504a9a9c6f89325f54958ee SHA-256: c1da6544fdf78420d61c6176ee77086fef5972dc24f7f8389a07e63672b7a222
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript triggered by the OpenAction, which utilizes the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). The JavaScript is obfuscated and uses String.fromCharCode, indicating an attempt to hide malicious code. This technique is commonly used to download and execute further stages of malware. The heuristics strongly suggest exploitation of a known PDF vulnerability.

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
e865664dfe48044bca9ed4c73f0b4f4849ff3c62ce46472e3fd5b796c6a3aa16
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 14227 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
a09b518cbc501b1b0696f1ca14101e59bb6b241af6a1003d6c19c8c235226253
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).