Firefox Vulnerability Exploited

Shakespeare's Sister points us to this article detailing the security flaw.

Specifically:

The two unpatched flaws in the Mozilla browser could allow an attacker to take control of your system.

A patch is expected shortly, but in the meantime users can protect themselves by switching off JavaScript. In addition, the Mozilla Foundation has now made the flaws effectively impossible to exploit by changes to the server-side download mechanism on the update.mozilla.org and addons.mozilla.org sites, according to security experts.

The flaws were confidentially reported to the Foundation on May 2, but by Saturday details had been leaked and were reported by several security organizations, including the French Security Incident Response Team (FrSIRT). Danish security firm Secunia marked the exploit as "extremely critical", its most serious rating, the first time it has given a Firefox flaw this rating.

In recent months Firefox has gained significant market share from Microsoft's Internet Explorer, partly because it is considered less vulnerable to attacks. However, industry observers have long warned that the browser is more secure partly because of its relatively small user base. As Firefox's profile grows, attackers will increasingly target the browser.