.. Copyright (C) Internet Systems Consortium, Inc. ("ISC")
..
.. SPDX-License-Identifier: MPL-2.0
..
.. This Source Code Form is subject to the terms of the Mozilla Public
.. License, v. 2.0.  If a copy of the MPL was not distributed with this
.. file, you can obtain one at https://mozilla.org/MPL/2.0/.
..
.. See the COPYRIGHT file distributed with this work for additional
.. information regarding copyright ownership.

Notes for BIND 9.16.37
----------------------

Security Fixes
~~~~~~~~~~~~~~

- An UPDATE message flood could cause :iscman:`named` to exhaust all
  available memory. This flaw was addressed by adding a new
  ``update-quota`` option that controls the maximum number of
  outstanding DNS UPDATE messages that :iscman:`named` can hold in a
  queue at any given time (default: 100). (CVE-2022-3094)

  ISC would like to thank Rob Schulhof from Infoblox for bringing this
  vulnerability to our attention. :gl:`#3523`

- :iscman:`named` could crash with an assertion failure when an RRSIG
  query was received and ``stale-answer-client-timeout`` was set to a
  non-zero value. This has been fixed. (CVE-2022-3736)

  ISC would like to thank Borja Marcos from Sarenet (with assistance by
  Iratxe Niño from Fundación Sarenet) for bringing this vulnerability to
  our attention. :gl:`#3622`

- :iscman:`named` running as a resolver with the
  ``stale-answer-client-timeout`` option set to any value greater than
  ``0`` could crash with an assertion failure, when the
  ``recursive-clients`` soft quota was reached. This has been fixed.
  (CVE-2022-3924)

  ISC would like to thank Maksym Odinintsev from AWS for bringing this
  vulnerability to our attention. :gl:`#3619`

New Features
~~~~~~~~~~~~

- The new ``update-quota`` option can be used to control the number of
  simultaneous DNS UPDATE messages that can be processed to update an
  authoritative zone on a primary server, or forwarded to the primary
  server by a secondary server. The default is 100. A new statistics
  counter has also been added to record events when this quota is
  exceeded, and the version numbers for the XML and JSON statistics
  schemas have been updated. :gl:`#3523`

Feature Changes
~~~~~~~~~~~~~~~

- The Differentiated Services Code Point (DSCP) feature in BIND has been
  deprecated. Configuring DSCP values in ``named.conf`` now causes a
  warning to be logged. Note that this feature has only been partly
  operational since the new Network Manager was introduced in BIND
  9.16.0. :gl:`#3773`

- The catalog zone implementation has been optimized to work with
  hundreds of thousands of member zones. :gl:`#3744`

Bug Fixes
~~~~~~~~~

- In certain query resolution scenarios (e.g. when following CNAME
  records), :iscman:`named` configured to answer from stale cache could
  return a SERVFAIL response despite a usable, non-stale answer being
  present in the cache. This has been fixed. :gl:`#3678`

Known Issues
~~~~~~~~~~~~

- There are no new known issues with this release. See :ref:`above
  <relnotes_known_issues>` for a list of all known issues affecting this
  BIND 9 branch.