SB2018052101 - Denial of service in ISC BIND

The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists on the systems that permit recursion to clients and that have the max-stale-ttl parameter set to a non-zero value due to a flaw in the serve-stale implementation even when serve-stale is not enabled. A remote attacker can trigger an assertion failure in rbtdb.c cause performance degradation on the target system such as recursion loops or excessive logging.

The vulnerability allows a remote authenticated attacker to cause DoS condition on the target system.

The weakness exists due to an error in zone database reference counting. A remote authenticated attacker who is able to cause the target server to initiate zone transfers (e.g., can send NOTIFY messages) can cause several transfers of a slave zone in quick succession to trigger an assertion in 'rbtdb.c' and cause 'named' to crash.