Malicious PDF — malware analysis report

Static analysis result for SHA-256 d56a031eed5976d9…

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: 1d7ecae43eb51205d352ce538e6353b9 SHA-1: d4127b431ad5e19e87c827392df7c7f2e94291ca SHA-256: d56a031eed5976d96ff276c121ea4e8c6726b9bb0e1143b4d222681dfa0836d1
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1071.001 Web Protocols

The PDF file contains embedded JavaScript triggered by an OpenAction, which is 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. The embedded JavaScript, particularly the 'numeric_charcode_stage_000.js' artifact, is heavily obfuscated but contains eval() calls and String.fromCharCode, suggesting it decodes and executes further malicious code. This likely leads to the download and execution of a second-stage payload.

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
3f834c91994a0df2c0bcef219b0239cb3580cab66ffe526c53c22181eec3c870
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
dca618f4a68adaad2e9e7aca066a28405be2efb5b69d7b778fcf34c9624e201b
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).