Usually, Microsoft releases all of its patches for Windows on the second Tuesday of the month but the software giant broke its monthly patch cycle this week to release a critical update for its operating systems.
The patch fixes a critical bug that allows attackers to do all sort of nasty things with your computer.
This security update resolves a privately reported vulnerability in the Server service. The vulnerability could allow remote code execution if an affected system received a specially crafted RPC request. On Microsoft Windows 2000, Windows XP, and Windows Server 2003 systems, an attacker could exploit this vulnerability without authentication to run arbitrary code. It is possible that this vulnerability could be used in the crafting of a wormable exploit. Firewall best practices and standard default firewall configurations can help protect network resources from attacks that originate outside the enterprise perimeter.
This security update is rated Critical for all supported editions of Microsoft Windows 2000, Windows XP, Windows Server 2003, and rated Important for all supported editions of Windows Vista and Windows Server 2008. For more information, see the subsection, Affected and Non-Affected Software, in this section.
You can download it through Windows Update, if your computer hasn't downloaded it automatically yet.