CVE-2009-0085: Microsoft Windows 2000

High severity, CVSS 7.1. EPSS: 15.2% chance of exploitation in the next 30 days.

The Secure Channel (aka SChannel) authentication component in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP1 and SP2, Vista Gold and SP1, and Server 2008, when certificate authentication is used, does not properly validate the client's key exchange data in Transport Layer Security (TLS) handshake messages, which allows remote attackers to spoof authentication by crafting a TLS packet based on knowledge of the certificate but not the private key, aka "SChannel Spoofing Vulnerability."

Affected products

• Microsoft Windows 2000: any version
• Microsoft Windows Server 2003: any version
• Microsoft Windows Server 2008: any version
• Microsoft Windows Vista: any version; version gold only
• Microsoft Windows XP: any version

Published 2009-03-10. Last modified 2026-06-16.