Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ca90ab11c8588ee…

MALICIOUS

PDF

12.1 KB Created: 2009-12-19 19:49:35 Authoring application: PDF Library 10.2.1 (via PDF Library 7.4.5)
MD5: 56282d931243d921b2cc00e40d078d8c SHA-1: 209762599c64ce95090a0aa4c6b6871667533133 SHA-256: 9ca90ab11c8588ee340b0e795b6e41c689e3864aa63fe83f66de17eebd9b14ec
278 Risk Score

Malware Insights

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

The PDF exploits multiple critical vulnerabilities in Adobe Reader, specifically CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992, by executing obfuscated JavaScript. The embedded JavaScript, identified as 'legacy_pdfkit_stage_000.js', is detected by ClamAV as 'Js.Exploit.Shellcode-18', indicating it likely downloads and executes a second-stage payload. The attack pattern is consistent with exploit kit delivery mechanisms targeting unpatched PDF readers.

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
af1eb1f4d252cd59c73de231851d5badb5a6bbee0aaddf14458d2997c2d6498b
pdf-javascript-stream PDF /JS object 7 at offset 0x268 38164 bytes
legacy_pdfkit_stage_000.js
47bcfbcac0697b4afdf280d8ece043ebfe70c53721783e07e5df7422f324f4c2
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x268 9880 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).