News is coming in that there is an outstanding security vulnerability in Mozilla Firefox and it has been confirmed by Mozilla's Window Snyder's blog.

Mozilla has rated this as a low severity bug so it doesn't seem like there is any immediate need for panic. It also only applies if Firefox has had certain add-ons installed. Two quoted as vulnerable are Statusbar and Greasemonkey. The problem might allow an attacker to see what software is installed on a computer.

According to one of the comments, the extension NoScript can protect a computer. I've not confirmed this but it's certainly better than nothing. Alternatively you could use a different browser like Opera until the bug is fixed