Release Notes for BIND Version 9.12.2-P1

Introduction

This document summarizes changes since the last production release on the
BIND 9.12 branch. Please see the CHANGES for a further list of bug fixes
and other changes.

Download

The latest versions of BIND 9 software can always be found at http://
www.isc.org/downloads/. There you will find additional information about
each release, source code, and pre-compiled versions for Microsoft Windows
operating systems.

Security Fixes

  * named could crash during recursive processing of DNAME records when
    deny-answer-aliases was in use. This flaw is disclosed in
    CVE-2018-5740. [GL #387]

  * When recursion is enabled but the allow-recursion and
    allow-query-cache ACLs are not specified, they should be limited to
    local networks, but they were inadvertently set to match the default
    allow-query, thus allowing remote queries. This flaw is disclosed in
    CVE-2018-5738. [GL #309]

  * The serve-stale feature could cause an assertion failure in rbtdb.c
    even when stale-answer-enable was false. The simultaneous use of stale
    cache records and NSEC aggressive negative caching could trigger a
    recursion loop in the named process. This flaw is disclosed in
    CVE-2018-5737. [GL #185]

  * A bug in zone database reference counting could lead to a crash when
    multiple versions of a slave zone were transferred from a master in
    close succession. This flaw is disclosed in CVE-2018-5736. [GL #134]

New Features

  * update-policy rules that otherwise ignore the name field now require
    that it be set to "." to ensure that any type list present is properly
    interpreted. Previously, if the name field was omitted from the rule
    declaration but a type list was present, it wouldn't be interpreted as
    expected.

  * named now supports the "root key sentinel" mechanism. This enables
    validating resolvers to indicate which trust anchors are configured
    for the root, so that information about root key rollover status can
    be gathered. To disable this feature, add root-key-sentinel no; to
    named.conf. [GL #37]

  * Add the ability to not return a DNS COOKIE option when one is present
    in the request. To prevent a cookie being returned add answer-cookie
    no; to named.conf. [GL #173]

    answer-cookie no is only intended as a temporary measure, for use when
    named shares an IP address with other servers that do not yet support
    DNS COOKIE. A mismatch between servers on the same address is not
    expected to cause operational problems, but the option to disable
    COOKIE responses so that all servers have the same behavior is
    provided out of an abundance of caution. DNS COOKIE is an important
    security mechanism, and should not be disabled unless absolutely
    necessary.

Feature Changes

  * BIND now can be compiled against libidn2 library to add IDNA2008
    support. Previously BIND only supported IDNA2003 using (now obsolete)
    idnkit-1 library.

  * dig +noidnin can be used to disable IDN processing on the input domain
    name, when BIND is compiled with IDN support.

Bug Fixes

  * named now rejects excessively large incremental (IXFR) zone transfers
    in order to prevent possible corruption of journal files which could
    cause named to abort when loading zones. [GL #339]

License

BIND is open source software licenced under the terms of the Mozilla
Public License, version 2.0 (see the LICENSE file for the full text).

The license requires that if you make changes to BIND and distribute them
outside your organization, those changes must be published under the same
license. It does not require that you publish or disclose anything other
than the changes you have made to our software. This requirement does not
affect anyone who is using BIND, with or without modifications, without
redistributing it, nor anyone redistributing BIND without changes.

Those wishing to discuss license compliance may contact ISC at https://
www.isc.org/mission/contact/.

End of Life

The end-of-life date for BIND 9.12 has not yet been determined. However,
it is not intended to be an Extended Support Version (ESV) branch;
accordingly, support will end after the next stable branch (9.14) becomes
available. Those needing a longer-lived branch are encouraged to use the
current ESV, BIND 9.11, which will be supported until December 2021. See
https://www.isc.org/downloads/software-support-policy/ for details of
ISC's software support policy.

Thank You

Thank you to everyone who assisted us in making this release possible. If
you would like to contribute to ISC to assist us in continuing to make
quality open source software, please visit our donations page at http://
www.isc.org/donate/.
