Microsoft has released 5 new security-focused updates for NT-Based operating systems, including Windows 2000 and Windows XP. All updates are labeled as "Important", and should be applied as soon as possible.
3 Updates are applicable to users of Windows XP SP2
Microsoft Security Bulletin MS04-041
Vulnerability in WordPad Could Allow Code Execution (KB885836)
Microsoft Security Bulletin MS04-042
Vulnerability in DHCP Could Allow Remote Code Execution and Denial of Service (KB885249) (NT4 Only)
Microsoft Security Bulletin MS04-043
Vulnerability in HyperTerminal Could Allow Code Execution (KB873339)
Microsoft Security Bulletin MS04-044
Vulnerabilities in Windows Kernel and LSASS Could Allow Elevation of Privilege (KB885835)
Microsoft Security Bulletin MS04-045
Vulnerability in WINS Could Allow Remote Code Execution (KB870763) (XP/2000 Not Effected)