Introduction

   BIND 9.7.7 is the latest production release of BIND 9.7.

   This document summarizes changes from BIND 9.7.6 to BIND 9.7.7.
   Please see the CHANGES file in the source code release for a
   complete list of all changes.

Download

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

Support

   Product support information is available on
   http://www.isc.org/services/support for paid support options. Free
   support is provided by our user community via a mailing list.
   Information on all public email lists is available at
   https://lists.isc.org/mailman/listinfo.

Security Fixes

*  A deliberately constructed combination of records could cause
   named to hang while populating the additional section of a
   response. [CVE-2012-5166] [RT #31090]

*  Prevents a named assert (crash) when queried for a record whose
   RDATA exceeds 65535 bytes  [CVE-2012-4244]  [RT #30416]

*  Prevents a named assert (crash) when validating caused by using
   "Bad cache" data before it has been initialized. [CVE-2012-3817]
   [RT #30025]

*  A condition has been corrected where improper handling of
   zero-length RDATA could cause undesirable behavior, including
   termination of the named process. [CVE-2012-1667]  [RT #29644]

New Features

*  None

Feature Changes

*  Improves OpenSSL error logging [RT #29932]

*  nslookup now returns a nonzero exit code when it is unable to get
   an answer.  [RT #29492]

Bug Fixes

*  Uses binary mode to open raw files on Windows.  [RT #30944]

*  Limits the TTL of signed RRsets in cache when their RRSIGs are
   approaching expiry. This prevents the persistence in cache of
   invalid RRSIGs in order to assist recovery from a situation where
   zone re-signing doesn't occur in a timely manner.   With this
   change, named will attempt to obtain new RRSIGs from the
   authoritative server once the original ones have expired, and even
   if the TTL of the old records would in other circumstances cause
   them to be kept in cache for longer.  [RT #26429]

*  The configure script now supports and detects libxml2-2.8.x
   correctly [RT #30440]

*  The host command should no longer assert on some architectures and
   builds while handling the time values used with the -w (wait
   forever) option.  [RT #18723]

*  Invalid zero settings for max-retry-time, min-retry-time,
   max-refresh-time, min-refresh-time will now be detected during
   parsing of named.conf and an error emitted instead of triggering an
   assertion failure on startup.  [RT #27730] 

*  Corrects the syntax of isc_atomic_xadd() and isc_atomic_cmpxchg()
   which are employed on Itanium systems to speed up lock management
   by making use of atomic operations.  Without the syntax correction
   it is possible that concurrent access to the same structures could
   accidentally occur with unpredictable results.  [RT #25181]

*  Removes spurious newlines from log messages in zone.c [RT #30675]

*  When built with readline support (i.e. on a system with readline
   installed) nsupdate no longer terminates unexpectedly in
   interactive mode. [RT #29550] 

*  Ensures that servers are expired from the ADB cache when the
   timeout limit is reached so that their learned attributes can be
   refreshed.  Prior to this change, servers that were frequently
   queried might never have their entries removed and reinitialized.
   This is of particular importance to DNSSEC-validating recursive
   servers that might erroneously set "no-edns" for an authoritative
   server following a period of intermittent connectivity. [RT #29856]

*  Adds additional resilience to a previous security change (3218) by
   preventing RRSIG data from being added to cache when a
   pseudo-record matching the covering type and proving non-existence
   exists at a higher trust level. The earlier change prevented this
   inconsistent data from being retrieved from cache in response to
   client queries  - with this additional change, the RRSIG records
   are no longer inserted into cache at all. [RT #26809]

*  dnssec-settime will now issue a warning when the writing of a new
   private key file would cause a change in the permissions of the
   existing file. [RT #27724]

*  Fixes the defect introduced by change #3314 that was causing
   failures when saving stub zones to disk (resulting in excessive CPU
   usage in some cases).  [RT #29952]

*  It is now possible to using multiple control keys again - this
   functionality was inadvertently broken by change #3924 (RT #28265)
   which addressed a memory leak. [RT #29694]

*  Reduces the potential build-up of stale RRsets in cache on a busy
   recursive nameserver by re-using cached DS and RRSIG rrsets when
   possible [RT #29446]

*  Upper-case/lower-case handling of RRSIG signer-names is now handled
   consistently: RRSIG records are generated with the signer-name in
   lower case. They are accepted with any case, but if they fail to
   validate, we try again in lower case. [RT #27451]

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/supportisc.

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