Malicious PDF — malware analysis report

Static analysis result for SHA-256 d74bc4cf0d28d9f3…

MALICIOUS

PDF

2.3 KB
MD5: d4555a1c569c472efcc32e6eccd7de88 SHA-1: 3d6ae3c582d0cce0e38dc5fcfb7ccd395411a8a6 SHA-256: d74bc4cf0d28d9f3f0fd4d329e7b111c0b1472a051c2b47a092335907e3e28b1
226 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains obfuscated JavaScript that utilizes `eval()` and `unescape()` functions, indicative of malicious intent. The critical heuristic `CVE_2009_0927` specifically points to the exploitation of a known vulnerability using the `Collab.getIcon` method. The embedded JavaScript streams, particularly `legacy_pdfkit_stage_000.js`, are likely responsible for downloading and executing a secondary payload, a common technique for malware delivery. The ClamAV detection further confirms its malicious nature.

Heuristics 8

  • 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)
  • ClamAV: Pdf.Exploit.Agent-36098 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36098
  • 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
e1ab3bbf30605cecdce6db9d2556198626dbb178f7a4cb471a9436bb6e8bd92f
pdf-javascript-stream PDF /JS object 111611 at offset 0x7F4 462 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
cbfbd38164e16441d4c1ca26dff0f6e645fc91b6fc61605eec46e91cef732f07
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2619 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).