Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5584d2a9ed54cfe…

MALICIOUS

PDF

1.9 KB
MD5: 6e1dfcd6a245b7d0f15eaa51eaeba04a SHA-1: a74fa5a4e675ab91df09a4a9061c639ab84258b3 SHA-256: f5584d2a9ed54cfecdbeb73863af5e203e42c35fcd34b4c2949062574f285372
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File

The PDF document contains embedded JavaScript that is heavily obfuscated using eval() and unescape() functions, along with String.fromCharCode. A critical heuristic identified the CVE-2009-0927 vulnerability (Collab.getIcon), indicating the script is designed to be launched automatically. The script's purpose is to download and execute a second-stage payload, as suggested by the obfuscation techniques and the nature of the exploit.

Heuristics 7

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (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 0x6CD 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
2bb2cec0abf5c40645f647f89103e2f97cffb5b12ce31dfdce7195c9dd691e43
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2637 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).