“managed-keys” is a feature which allows a BIND resolver to automatically maintain the keys used by trust anchors which operators configure for use in DNSSEC validation. Due to an error in the managed-keys feature it is possible for a BIND server which uses managed-keys to exit due to an assertion failure if, during key rollover, a trust anchor’s keys are replaced with keys which use an unsupported algorithm. Versions affected: BIND 9.9.0 -> 9.10.8-P1, 9.11.0 -> 9.11.5-P1, 9.12.0 -> 9.12.3-P1, and versions 9.9.3-S1 -> 9.11.5-S3 of BIND 9 Supported Preview Edition. Versions 9.13.0 -> 9.13.6 of the 9.13 development branch are also affected. Versions prior to BIND 9.9.0 have not been evaluated for vulnerability to CVE-2018-5745.

A failure to free memory can occur when processing messages having a specific combination of EDNS options. Versions affected are: BIND 9.10.7 -> 9.10.8-P1, 9.11.3 -> 9.11.5-P1, 9.12.0 -> 9.12.3-P1, and versions 9.10.7-S1 -> 9.11.5-S3 of BIND 9 Supported Preview Edition. Versions 9.13.0 -> 9.13.6 of the 9.13 development branch are also affected.

By design, BIND is intended to limit the number of TCP clients that can be connected at any given time. The number of allowed connections is a tunable parameter which, if unset, defaults to a conservative value for most servers. Unfortunately, the code which was intended to limit the number of simultaneous connections contained an error which could be exploited to grow the number of simultaneous connections beyond this limit. Versions affected: BIND 9.9.0 -> 9.10.8-P1, 9.11.0 -> 9.11.6, 9.12.0 -> 9.12.4, 9.14.0. BIND 9 Supported Preview Edition versions 9.9.3-S1 -> 9.11.5-S3, and 9.11.5-S5. Versions 9.13.0 -> 9.13.7 of the 9.13 development branch are also affected. Versions prior to BIND 9.9.0 have not been evaluated for vulnerability to CVE-2018-5743.

While backporting a feature for a newer branch of BIND9, RedHat introduced a path leading to an assertion failure in buffer.c:420. Affects RedHat versions bind-9.9.4-65.el7 -> bind-9.9.4-72.el7. No ISC releases are affected. Other packages from other distributions who made the same error may also be affected.

To provide fine-grained controls over the ability to use Dynamic DNS (DDNS) to update records in a zone, BIND 9 provides a feature called update-policy. Various rules can be configured to limit the types of updates that can be performed by a client, depending on the key used when sending the update request. Unfortunately, some rule types were not initially documented, and when documentation for them was added to the Administrator Reference Manual (ARM) in change #3112, the language that was added to the ARM at that time incorrectly described the behavior of two rule types, krb5-subdomain and ms-subdomain. This incorrect documentation could mislead operators into believing that policies they had configured were more restrictive than they actually were. This affects BIND versions prior to BIND 9.11.5 and BIND 9.12.3.

“deny-answer-aliases” is a little-used feature intended to help recursive server operators protect end users against DNS rebinding attacks, a potential method of circumventing the security model used by client browsers. However, a defect in this feature makes it easy, when the feature is in use, to experience an assertion failure in name.c. Affects BIND 9.7.0->9.8.8, 9.9.0->9.9.13, 9.10.0->9.10.8, 9.11.0->9.11.4, 9.12.0->9.12.2, 9.13.0->9.13.2.