Bugzilla is a web tool of Mozilla for report errors on a single platform. Depending on the error reported by the user this was common knowledge to the community or was restricted to Bugzilla administrators. An attacker stole the credentials of an administrator user so he had access to vulnerabilities affecting the Firefox browser. As reported by the Mozilla, the attacker use the information to attack the Firefox browser vulnerabilities. Firefox updated on August 27 a new browser version that corrects all the vulnerabilities that the attacker had access. Mozilla updated with a double authentication the Bugzilla tool for users with access to confidential information.