Ubuntu Security Notice 474-1 - It was discovered that xscreensaver did not correctly validate the return values from network authentication systems such as LDAP or NIS. A local attacker could bypass a locked screen if they were able to interrupt network connectivity.
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Gentoo Linux Security Advisory GLSA 200705-14 - XScreenSaver incorrectly handles the results of the getpwuid() function in drivers/lock.c when using directory servers during a network outage. Versions less than 5.02 are affected.
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Mandriva Linux Security Advisory - A problem with the way xscreensaver verifies user passwords was discovered by Alex Yamauchi. When a system is using remote authentication (i.e. LDAP) for logins, a local attacker able to cause a network outage on the system could cause xscreensaver to crash, which would unlock the screen.
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