Malicious PDF — malware analysis report

Static analysis result for SHA-256 99d746ca446e22e3…

MALICIOUS

PDF

9.0 KB Created: 2009-11-11 19:44:06 Authoring application: PDF Library 2.10.1 (via PDF Library 2.3.9)
MD5: 36f3f52bf71872d06f6c263d0e0f199f SHA-1: 08ca2fb29c4911c1cf567a87a8555edae2f9c4a4 SHA-256: 99d746ca446e22e3b55e1e3b0d44f76b83c479381378ef99d8f9d886b93914c6
278 Risk Score

Malware Insights

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

This PDF document exploits multiple known vulnerabilities in Adobe Reader, including CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992, by leveraging embedded JavaScript. The heuristics indicate that the JavaScript is obfuscated and likely decodes to a malicious payload. An extracted artifact, 'legacy_pdfkit_stage_000.js', was detected by ClamAV as 'Js.Exploit.Shellcode-18', further confirming its malicious nature. The primary attack pattern involves exploiting these vulnerabilities to achieve arbitrary code execution, likely for downloading and executing a secondary stage.

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)
  • 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)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • 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_obj0007_000.js
a916a5e4a7ccac738ef47d668484066fb4b723921647f431b741fa3f53c4da2e
pdf-javascript-stream PDF /JS object 7 at offset 0x268 37535 bytes
legacy_pdfkit_stage_000.js
60458b8c7f3389f67f8f1ee7fd7750cfcb985cf521dfb9c5106d162dab72c403
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x268 9868 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).