Mandriva Linux Security Advisory 2011-001 - ISC DHCP server 4.2 before 4.2.0-P2, when configured to use failover partnerships, allows remote attackers to cause a denial of service by connecting to a port that is only intended for a failover peer, as demonstrated by a Nagios check_tcp process check to TCP port 520. The updated packages have been patched to correct this issue.
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