Both Microsoft and Mozilla have released patches for their flagship browsers in the past 24 hours or so.

Microsoft’s patch was a response to a security hole that could allow an attacker to steal passwords from your computer using a drive-by download initiated on an infected site you might visit, or be sent to. Every version of IE, from IE5 to IE8 beta 2 is affected, so you should update immediately if you don’t use Automatic updates(or if you have it set for a long time in between updates).

Firefox versions 2 and 3 both had patches released too, though the security flaws fixed in FF were unrelated to the IE security flaw. So make sure you grab the latest version of either of those as well. Mozilla says this will be the last update to the 2.x codebase of Firefox.

Even if you don’t use either FF or IE as your primary browser, if you have either installed, update them immediately.