'Highly critical' flaw repaired

The Mozilla Corporation has released an update to its Firefox browser, repairing a vulnerability that exposed users to a denial of service attack.

Attackers could exploit the security hole by maliciously coding a website that causes the browser to crash. If unwitting users visit such a site it can compromise system security, allowing hackers to execute arbitrary code.

The flaw affects Firefox versions 1.5 through 1.5.0.3. Older clients are not affected.

Security website Secunia gave the flaw its second highest rating of 'highly critical'.

The update comes just three weeks after Mozilla released version 1.5.0.3 of the browser which plugged a series of security holes.

Current Firefox users will receive an automatic update notification or can manually apply the patch through the 'check for updates' function.