Link: http://www.theregister.co.uk/2010/01/19/microsoft_escalation_bug/

Every OS all the way from Windows NT is vulnerable. -There are workarounds, they are complicated for the general user, and you'll not be running anything in true dos fashion. (this won't be a problem unless you are a true geek)

The vulnerability exists in all 32-bit versions of Microsoft OSes released since 1993, and proof-of-concept code works on the XP, Server 2003, Vista, Server 2008, and 7 versions of Windows, Ormandy reported. Presumably, Windows 2000 is also susceptible.

Ormandy said the security hole can easily be closed by turning off the MSDOS and WOWEXEC subsystems. The changes generally don't interfere with most tasks since they disable rarely-used 16-bit applications. He said he informed Microsoft security employees of the vulnerability in June.

"Regrettably, no official patch is currently available," he wrote. "As an effective and easy to deploy workaround is available, I have concluded that it is in the best interest of users to go ahead with the publication of this document without an official patch."

Follow the article for the workaround - wonder if this will cause problems with Dosbox or not?