MS09-064  Vulnerability in License Logging Server Could Allow Remote Code Execution (974783)

Critical - Remote Code Execution This security update resolves a privately reported vulnerability in Microsoft Windows 2000. The vulnerability could allow remote code execution if an attacker sent a specially crafted network message to a computer running the License Logging Server. An attacker who successfully exploited this vulnerability could take complete control of the system. Firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter.
Bulletin details at Microsoft.com