MS09-054 addresses an IE vulnerability (CVE-2009-2529), which was discovered and presented by Mark Dowd, Ryan Smith, and David Dewey at the BlackHat conference in July.
First we’d like to make it clear that any customers that have applied the update associated with MS09-054 are protected, regardless of the attack vector. And most customers need not take any action as they’ll receive this update automatically through Automatic Updates.