https://developer.mozilla.org/devnews/index.php/2011/03/22/firefox-3-6-16-and-3-5-18-security-updates-now-available/

http://blog.mozilla.com/security/2011/03/22/firefox-blocking-fraudulent-certificates/
« This issue was reported to us by the Comodo Group »

https://blog.torproject.org/blog/detecting-certificate-authority-compromises-and-web-browser-collusion