Last week, the Mozilla organization released a new version, 23.0, of its Firefox browser, for all platforms (Linux, Windows, and Mac OS X). The new version fixes 13 identified security vulnerabilities. Mozilla rates four of these as being of Critical severity, and seven as High severity.
In addition, the new version introduces some new and changed capabilities. It incorporates mixed content blocking, to protect against eavesdropping and “man-in-the-middle” attacks on secure pages. It also incorporates a new Options panel for the Web Developer Toolbox.
Mozilla also released a new version, 17.0.8, of its Thunderbird E-mail client for Linux, Windows, and Mac OS X. This is a security release, which fixes eight identified vulnerabilities; Mozilla rates two of these as Critical, and six as High severity. For more information, see the Thunderbird Release Notes.
As with Firefox, you can obtain the new version via the built-in update mechanism, or download a complete installation package.
Because of the security content of these releases, I recommend that you upgrade your systems if you have not already done so.