Release Notes for BIND Version 9.11.5-P1

Introduction

This document summarizes changes since the last production release on the
BIND 9.11 (Extended Support Version) branch. Please see the CHANGES file
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.

License Change

With the release of BIND 9.11.0, ISC changed to the open source license
for BIND from the ISC license to the Mozilla Public License (MPL 2.0).

The MPL-2.0 license requires that if you make changes to licensed software
(e.g. BIND) and distribute them outside your organization, that you
publish those changes under that same license. It does not require that
you publish or disclose anything other than the changes you made to our
software.

This requirement will not affect anyone who is using BIND, with or without
modifications, without redistributing it, nor anyone redistributing it
without changes. Therefore, this change will be without consequence for
most individuals and organizations who are using BIND.

Those unsure whether or not the license change affects their use of BIND,
or who wish to discuss how to comply with the license may contact ISC at
https://www.isc.org/mission/contact/.

Legacy Windows No Longer Supported

As of BIND 9.11.2, Windows XP and Windows 2003 are no longer supported
platforms for BIND; "XP" binaries are no longer available for download
from ISC.

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]

  * Code change #4964, intended to prevent double signatures when deleting
    an inactive zone DNSKEY in some situations, introduced a new problem
    during zone processing in which some delegation glue RRsets are
    incorrectly identified as needing RRSIGs, which are then created for
    them using the current active ZSK for the zone. In some, but not all
    cases, the newly-signed RRsets are added to the zone's NSEC/NSEC3
    chain, but incompletely -- this can result in a broken chain,
    affecting validation of proof of nonexistence for records in the zone.
    [GL #771]

New Features

  * 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.

  * Added the ability not to 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.

  * Two new update policy rule types have been added krb5-selfsub and
    ms-selfsub which allow machines with Kerberos principals to update the
    name space at or below the machine names identified in the respective
    principals.

Removed Features

  * named will now log a warning if the old BIND now can be compiled
    against libidn2 library to add IDNA2008 support. Previously BIND only
    supported IDNA2003 using (now obsolete) idnkit-1 library.

Feature Changes

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

  * Multiple cookie-secret clause are now supported. The first
    cookie-secret in named.conf is used to generate new server cookies.
    Any others are used to accept old server cookies or those generated by
    other servers using the matching cookie-secret.

  * The rndc nta command could not differentiate between views of the same
    name but different class; this has been corrected with the addition of
    a -class option. [GL #105]

Bug Fixes

  * When a negative trust anchor was added to multiple views using rndc
    nta, the text returned via rndc was incorrectly truncated after the
    first line, making it appear that only one NTA had been added. This
    has been fixed. [GL #105]

  * 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]

  * rndc reload could cause named to leak memory if it was invoked before
    the zone loading actions from a previous rndc reload command were
    completed. [RT #47076]

End of Life

BIND 9.11 (Extended Support Version) will be supported until at least
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/.
