Mozilla has released Firefox 3.5.8 and Firefox 3.0.18 for Windows, Mac and Linux, patching five vulnerabilities, three of which are rated 'critical'.
Mike Beltzner, Mozilla's director of Firefox, said in an update notification that the new versions are part of an ongoing stability and security update process.
Some of the patches apply to critical issues, which could lead to a hacker taking remote control of an affected system.
Mozilla said that the rating applied to vulnerabilities that can be "used to run attacker code and install software, requiring no user interaction beyond normal browsing".
Other fixes relate to bugs such as application crashes, something that seems to be prevalent when running Privacy mode, and during profile management when switching from Safari.
"We strongly recommend that all Firefox users upgrade to this latest release. If you already have Firefox 3.5 or Firefox 3, you will receive an automated update notification within 24 to 48 hours," said Beltzner.
"This update can also be applied manually by selecting 'Check for Updates' from the Help menu."
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