The resolver in ISC BIND 9 through 9.8.1-P1 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.

query.c in ISC BIND 9.0.x through 9.6.x, 9.4-ESV through 9.4-ESV-R5, 9.6-ESV through 9.6-ESV-R5, 9.7.0 through 9.7.4, 9.8.0 through 9.8.1, and 9.9.0a1 through 9.9.0b1 allows remote attackers to cause a denial of service (assertion failure and named exit) via unknown vectors related to recursive DNS queries, error logging, and the caching of an invalid record by the resolver.