Netcraft has released its security toolbar for the open source Firefox browser, aiming to limit the threat from phishing scams by using a blacklist of known fraudulent websites.

The technology relies on individuals earmarking the URLs of phishing websites and passing the information on to other users. The toolbar then blocks access to the sites.

It also makes sure that the browser displays all the toolbars. Some phishing sites hide the URL to prevent users from noticing that the URL of the fraudulent site differs from the legitimate version.

The toolbar provides users with information on the site's hosting location, allowing them to confirm that the barclays.co.uk website, for example, is really hosted in the UK and not in some Soviet republic.

By displaying the country where the server is located, a user can more easily spot a fraudulent internet address.

The toolbar supports Internet Explorer running on Windows XP and Firefox version 1.0 and later for any of the supported operating systems, including Windows, Linux and Mac OS.

The toolbar is free of charge and can be downloaded here.