.. 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 9.18.1 --------------------- Security Fixes ~~~~~~~~~~~~~~ - The rules for acceptance of records into the cache have been tightened to prevent the possibility of poisoning if forwarders send records outside the configured bailiwick. (CVE-2021-25220) ISC would like to thank Xiang Li, Baojun Liu, and Chaoyi Lu from Network and Information Security Lab, Tsinghua University, and Changgen Zou from Qi An Xin Group Corp. for bringing this vulnerability to our attention. :gl:`#2950` - TCP connections with :any:`keep-response-order` enabled could leave the TCP sockets in the ``CLOSE_WAIT`` state when the client did not properly shut down the connection. (CVE-2022-0396) :gl:`#3112` - Lookups involving a DNAME could trigger an assertion failure when :any:`synth-from-dnssec` was enabled (which is the default). (CVE-2022-0635) ISC would like to thank Vincent Levigneron from AFNIC for bringing this vulnerability to our attention. :gl:`#3158` - When chasing DS records, a timed-out or artificially delayed fetch could cause ``named`` to crash while resuming a DS lookup. (CVE-2022-0667) :gl:`#3129` Feature Changes ~~~~~~~~~~~~~~~ - The DLZ API has been updated: EDNS Client-Subnet (ECS) options sent by a client are now included in the client information sent to DLZ modules when processing queries. :gl:`#3082` - DEBUG(1)-level messages were added when starting and ending the BIND 9 task-exclusive mode that stops normal DNS operation (e.g. for reconfiguration, interface scans, and other events that require exclusive access to a shared resource). :gl:`#3137` - The limit on the number of simultaneously processed pipelined DNS queries received over TCP has been removed. Previously, it was capped at 23 queries processed at the same time. :gl:`#3141` Bug Fixes ~~~~~~~~~ - A failed view configuration during a ``named`` reconfiguration procedure could cause inconsistencies in BIND internal structures, causing a crash or other unexpected errors. This has been fixed. :gl:`#3060` - Previously, ``named`` logged a "quota reached" message when it hit its hard quota on the number of connections. That message was accidentally removed but has now been restored. :gl:`#3125` - The :any:`max-transfer-time-out` and :any:`max-transfer-idle-out` options were not implemented when the BIND 9 networking stack was refactored in 9.16. The missing functionality has been re-implemented and outgoing zone transfers now time out properly when not progressing. :gl:`#1897` - TCP connections could hang indefinitely if the other party did not read sent data, causing the TCP write buffers to fill. This has been fixed by adding a "write" timer. Connections that are hung while writing now time out after the :any:`tcp-idle-timeout` period has elapsed. :gl:`#3132` - Client TCP connections are now closed immediately when data received cannot be parsed as a valid DNS request. :gl:`#3149` - The statistics counter representing the current number of clients awaiting recursive resolution results (``RecursClients``) could be miscalculated in certain resolution scenarios, potentially causing the value of the counter to drop below zero. This has been fixed. :gl:`#3147` - An error in the processing of the :any:`blackhole` ACL could cause some DNS requests sent by :iscman:`named` to fail - for example, zone transfer requests and SOA refresh queries - if the destination address or prefix was specifically excluded from the ACL using ``!``, or if the ACL was set to ``none``. This has now been fixed. :any:`blackhole` worked correctly when it was left unset, or if only positive-match elements were included. :gl:`#3157` - Build errors were introduced in some DLZ modules due to an incomplete change in the previous release. This has been fixed. :gl:`#3111` Known Issues ~~~~~~~~~~~~ - There are no new known issues with this release. See :ref:`above ` for a list of all known issues affecting this BIND 9 branch.