Mozilla's Firefox 2 and Microsoft's Internet Explorer 7 <A HREF="http://news.zdnet.com/2100-1009_22-6137844.html?tag=nl.r23660">are vulnerable to a flaw</A> that could allow attackers to steal passwords. Dubbed a reverse cross-site request, or RCSR, vulnerability by its discoverer, Robert Chapin, the flaw lets hackers compromise users' passwords and usernames by presenting them with a fake login form. Firefox Password Manager will automatically enter any saved passwords and usernames into the form. The data is then automatically sent to an attacker's computer without the user's knowledge, according to the Chapin Information Services site.