The resolver in MaraDNS before 1.3.0.7.15 and 1.4.x before 1.4.12 overwrites cached server names and TTL values in NS records during the processing of a response to an A record query, which allows remote attackers to trigger continued resolvability of revoked domain names via a "ghost domain names" attack.
https://exchange.xforce.ibmcloud.com/vulnerabilities/74119
https://bugzilla.redhat.com/show_bug.cgi?id=804770
http://www.securitytracker.com/id?1026821
http://www.openwall.com/lists/oss-security/2012/03/20/10
http://www.openwall.com/lists/oss-security/2012/03/20/1