Back in 2004, Microsoft made the decision to release all security updates for all of their products on the second Tuesday of each month, a day now known to us IT folk as “Patch Tuesday”.
Occasionally, Microsoft will release an “out of band” or “emergency” patch outside of the “Patch Tuesday” schedule. They do this because the security issue in question is simply too critical to wait until the next Patch Tuesday.
There is a new vulnerability out there that affects the “server” service on Windows 2000, Windows XP, Windows Server 2003 and Windows Server 2008 (both x86 and x64 versions). Microsoft released a new emergency patch for it today. You can read all the technical mumbo-jumbo about it here.
The important thing is that you run Windows Update (or Microsoft Update) on all of your computers ASAP. This exploit looks pretty nasty!