Release Notes for BIND Version 9.11.3
Introduction
This document summarizes changes since the last production release on
the BIND 9.11 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.
New DNSSEC Root Key
ICANN is in the process of introducing a new Key Signing Key (KSK) for
the global root zone. BIND has multiple methods for managing DNSSEC
trust anchors, with somewhat different behaviors. If the root key is
configured using the managed-keys statement, or if the pre-configured
root key is enabled by using dnssec-validation auto, then BIND can keep
keys up to date automatically. Servers configured in this way should
have begun the process of rolling to the new key when it was published
in the root zone in July 2017. However, keys configured using the
trusted-keys statement are not automatically maintained. If your server
is performing DNSSEC validation and is configured using trusted-keys,
you are advised to change your configuration before the root zone
begins signing with the new KSK. This is currently scheduled for
October 11, 2017.
This release includes an updated version of the bind.keys file
containing the new root key. This file can also be downloaded from
https://www.isc.org/bind-keys .
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
* An error in TSIG handling could permit unauthorized zone transfers
or zone updates. These flaws are disclosed in CVE-2017-3142 and
CVE-2017-3143. [RT #45383]
* The BIND installer on Windows used an unquoted service path, which
can enable privilege escalation. This flaw is disclosed in
CVE-2017-3141. [RT #45229]
* With certain RPZ configurations, a response with TTL 0 could cause
named to go into an infinite query loop. This flaw is disclosed in
CVE-2017-3140. [RT #45181]
* Addresses could be referenced after being freed during resolver
processing, causing an assertion failure. The chances of this
happening were remote, but the introduction of a delay in
resolution increased them. This bug is disclosed in CVE-2017-3145.
[RT #46839]
* 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. If the name field was omitted from the
rule declaration and a type list was present it wouldn't be
interpreted as expected.
Removed Features
* The ISC DNSSEC Lookaside Validation (DLV) service has been shut
down; all DLV records in the dlv.isc.org zone have been removed.
References to the service have been removed from BIND
documentation. Lookaside validation is no longer used by default by
delv. The DLV key has been removed from bind.keys. Setting
dnssec-lookaside to auto or to use dlv.isc.org as a trust anchor
results in a warning being issued.
* named will now log a warning if the old root DNSSEC key is
explicitly configured and has not been updated. [RT #43670]
Protocol Changes
* BIND can now use the Ed25519 and Ed448 Edwards Curve DNSSEC signing
algorithms described in RFC 8080. Note, however, that these
algorithms must be supported in OpenSSL; currently they are only
available in the development branch of OpenSSL at
https://github.com/openssl/openssl. [RT #44696]
* When parsing DNS messages, EDNS KEY TAG options are checked for
correctness. When printing messages (for example, in dig), EDNS KEY
TAG options are printed in readable format.
Feature Changes
* named will no longer start or accept reconfiguration if
managed-keys or dnssec-validation auto are in use and the
managed-keys directory (specified by managed-keys-directory, and
defaulting to the working directory if not specified), is not
writable by the effective user ID. [RT #46077]
* Previously, update-policy local; accepted updates from any source
so long as they were signed by the locally-generated session key.
This has been further restricted; updates are now only accepted
from locally configured addresses. [RT #45492]
* dig +ednsopt now accepts the names for EDNS options in addition to
numeric values. For example, an EDNS Client-Subnet option could be
sent using dig +ednsopt=ecs:.... Thanks to John Worley of Secure64
for the contribution. [RT #44461]
* Threads in named are now set to human-readable names to assist
debugging on operating systems that support that. Threads will have
names such as "isc-timer", "isc-sockmgr", "isc-worker0001", and so
on. This will affect the reporting of subsidiary thread names in ps
and top, but not the main thread. [RT #43234]
* DiG now warns about .local queries which are reserved for Multicast
DNS. [RT #44783]
Bug Fixes
* Attempting to validate improperly unsigned CNAME responses from
secure zones could cause a validator loop. This caused a delay in
returning SERVFAIL and also increased the chances of encountering
the crash bug described in CVE-2017-3145. [RT #46839]
* When named was reconfigured, failure of some zones to load
correctly could leave the system in an inconsistent state; while
generally harmless, this could lead to a crash later when using
rndc addzone. Reconfiguration changes are now fully rolled back in
the event of failure. [RT #45841]
* Fixed a bug that was introduced in an earlier development release
which caused multi-packet AXFR and IXFR messages to fail validation
if not all packets contained TSIG records; this caused
interoperability problems with some other DNS implementations. [RT
#45509]
* Reloading or reconfiguring named could fail on some platforms when
LMDB was in use. [RT #45203]
* Due to some incorrectly deleted code, when BIND was built with
LMDB, zones that were deleted via rndc delzone were removed from
the running server but were not removed from the new zone database,
so that deletion did not persist after a server restart. This has
been corrected. [RT #45185]
* Semicolons are no longer escaped when printing CAA and URI records.
This may break applications that depend on the presence of the
backslash before the semicolon. [RT #45216]
* AD could be set on truncated answer with no records present in the
answer and authority sections. [RT #45140]
* Some header files included <isc/util.h> incorrectly as it pollutes
with namespace with non ISC_ macros and this should only be done by
explicitly including <isc/util.h>. This has been corrected. Some
code may depend on <isc/util.h> being implicitly included via other
header files. Such code should explicitly include <isc/util.h>.
* Zones created with rndc addzone could temporarily fail to inherit
the allow-transfer ACL set in the options section of named.conf.
[RT #46603]
* named failed to properly determine whether there were active KSK
and ZSK keys for an algorithm when update-check-ksk was true (which
is the default setting). This could leave records unsigned when
rolling keys. [RT #46743] [RT #46754] [RT #46774]
End of Life
The end of life for BIND 9.11 is yet to be determined but will not be
before BIND 9.13.0 has been released for 6 months.
https://www.isc.org/downloads/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/.