Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7057526eea89bb2…

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: a9e644e956c97441c41d91580099e32d SHA-1: e0a9571769c50f9d2ce6c7cf3bc8f637ec5de962 SHA-256: c7057526eea89bb214dd89a8b9b83dfc0b4c93c540348f4ba3b28f3156b98776
166 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript that is triggered by the OpenAction feature. The JavaScript utilizes eval() and String.fromCharCode, indicating obfuscation. The critical CVE-2007-5659 heuristic firing points to the use of Collab.collectEmailInfo, a known method for exploiting PDF vulnerabilities to execute arbitrary code. The script is likely designed to download and execute 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
92daecbc23c8cfa4783b9b9512fcccbde9d1047af73af69c4721605f90f91d9f
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 13543 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
543d3cd7cd9e017c3f8be98273185f8804c9d027b3b251f42659c7b93b272864
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).