Ubuntu Security Notice 537-2 - USN-537-1 fixed vulnerabilities in gnome-screensaver. The fixes were incomplete, and only reduced the scope of the vulnerability, without fully solving it. This update fixes related problems in compiz.
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Ubuntu Security Notice 537-1 - Jens Askengren discovered that gnome-screensaver became confused when running under Compiz, and could lose keyboard lock focus. A local attacker could exploit this to bypass the user's locked screen saver.
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