Microsoft » Windows 2000 : Security Vulnerabilities, CVEs, Published In May 2001 (Denial of service)

Windows 2000 allows local users to cause a denial of service and possibly gain privileges by setting a hardware breakpoint that is handled using global debug registers, which could cause other processes to terminate due to an exception, and allow hijacking of resources such as named pipes.

Windows 98 and Windows 2000 Java clients allow remote attackers to cause a denial of service via a Java applet that opens a large number of UDP sockets, which prevents the host from establishing any additional UDP connections, and possibly causes a crash.