Mozilla has released critical security updates to its Firefox browser, its Thunderbird e-mail client, and its SeaMonkey application suite.
The flaws addressed by the updates could expose users' sensitive information to remote hackers.
Users are being advised to update their Firefox browser to version 3.0.5, which was released this week.
They are also advised to update to version 188.8.131.52 of Thunderbird and version 1.1.14 of SeaMonkey.
The browser vulnerabilities were found in earlier versions of Firefox 3, as well as in versions of Firefox 2.
Microsoft updated its own Internet Explorer browser with an "out of cycle" critical security patch earlier this week.