Risk: Medium
Microsoft's regular monthly patch delivery slipped quietly onto the net carrying five new patches in December, each described by Redmond as "important".
First up there's a flaw (MS04-041) in WordPad that potentially allows malicious code to be executed. All flavours of Windows (XP, 2000, 2003 and NT) need patching. A rare vulnerability (MS04-043) in the HyperTerminal component of Windows similarly affects all versions of Windows.
But a security bug in DHCP (Dynamic Host Configuration Protocol) that might allow remote code execution and denial of service affects only Windows NT (MS04-042).
Next in queue are vulnerabilities in the Windows Kernel and Local Security Authority Subsystem (LSASS), which create a means for hackers to elevate their privileges (MS04-044). Again all versions of Windows are affected.
Lastly, a vulnerability in Windows Internet Naming Service (WINS) that could allow remote code execution (MS04-045).
Buffer overflow bugs are the culprits for almost all of these vulnerabilities.
Microsoft's most important December 2004 patch came earlier in the month when it broke with its normal cycle to release a fix for the IFRAME vulnerability in IE, infamously exploited by the Bofra worm. Unsurprisingly this fix (MS04-040) is a "critical" update for all versions of Windows bar Win XP SP2 and Windows 2003.