WebProNews

An email advisory to the volunteers who have registered on the site have been advised to update their logins.

The Mozilla Foundation believes someone exploited a problem in the site's content management software to access the site. Mozilla both develops the Firefox browser and maintains the Spread Firefox web site.

"It appears that a part of Spread Firefox was hacked in an attempt to use it to send out spam. It doesn't look like the attacker accessed any personal data on the site, but to be safe, we're encouraging all of our users to log in and change their passwords," wrote Asa Dotzler.

"If you have an account with Spread Firefox, you probably received an email about this with instructions for updating your password."

Volunteers had contributed information like email addresses and street addresses to the site. But it appears those attacking the site were seeking a conduit to send out junk messages.

The Firefox browser has gained more market share among web users. A recent study shows it has over 8 percent of market share, and looks like it is getting close to 10 percent. Microsoft's Internet Explorer still leads in market share.

The intrusion poses some embarrassment for Firefox supporters, who have long claimed their browser was more secure than IE. On Monday, links to forums, blogs, and other destinations do not appear to be working on the Spread Firefox site.

David Utter is a staff writer for WebProNews covering technology and business. Email him here.