A denial of service flaw was found in the way BIND handled a query response containing CNAME or DNAME resource records in an unusual order. A remote attacker could use this flaw to make named exit unexpectedly with an assertion failure via a specially crafted DNS response. A denial of service flaw was found in the way BIND handled query requests when using DNS64 with "break-dnssec yes" option. A remote attacker could use this flaw to make named exit unexpectedly with an assertion failure via a specially crafted DNS request. Upstream acknowledges Oleg Gorokhov as the original reporter of CVE-2017-3136 .