Malicious PDF — malware analysis report

Static analysis result for SHA-256 e128e5056617109f…

MALICIOUS

PDF

1.9 KB
MD5: 54098f99f7190dae7a533ea7b6384a31 SHA-1: d4c4b14ce641baebb1e0bbc2772ef8fe6cc9048d SHA-256: e128e5056617109f973b17d9a8b5731275458d75570e00cc010a7b330d43b158
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, which is obfuscated using `eval()` and `unescape()` functions. The critical heuristic firing indicates exploitation of CVE-2007-5659 via the `Collab.collectEmailInfo` method. This JavaScript is designed to be executed by a vulnerable PDF reader, likely to download and execute a secondary payload. No specific family could be identified, but the technique is common for initial access.

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)
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (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_obj111611_000.js
433d6141b5fc932a52d94051061c1f7566cbde37bb51ce636d76e20ed4ab2bf6
pdf-javascript-stream PDF /JS object 111611 at offset 0x6CF 297 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
b9db411028f87fbe97b720ff8071785b82d41ce92c2ae68a0f8945ebeb05037b
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2628 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).