the problems related to the handling of broken DNSSEC trust chains.
This fix is only relevant for those who have DNSSEC validation
enabled and configure trust anchors from third parties, either
manually, or through a system like DLV.
security patches to the 9.6.1 version, as well as many other bug fixes.
This version also incorporates a different fix for the problem we had
patched in contrib/bind9/bin/dig/dighost.c, so that file is now back
to being the same as the vendor version.
Due to the fact that the DNSSEC algorithm that will be used to sign the
root zone is only included in this version and in 9.7.x those who wish
to do validation MUST upgrade to one of these prior to July 2010.
related to DNSSEC validation on a resolving name server that allows
access to untrusted users. If your system does not fall into all 3 of
these categories you do not need to update immediately.
Receipt of a specially-crafted dynamic update message may
cause BIND 9 servers to exit. This vulnerability affects all
servers -- it is not limited to those that are configured to
allow dynamic updates. Access controls will not provide an
effective workaround.
More details can be found here: https://www.isc.org/node/474
All BIND users are encouraged to update to a patched version ASAP.
Approved by: re (re -> SO -> dougb)
changes from the 9.6.1rc1 version. The first 2 only affect DNSSEC.
named could incorrectly delete NSEC3 records for
empty nodes when processing a update request.
Accept DS responses from delegation only zones.
"delegation-only" was not being accepted in
delegation-only type zones.
lots of new features compared to 9.4.x, including:
Full NSEC3 support
Automatic zone re-signing
New update-policy methods tcp-self and 6to4-self
DHCID support.
More detailed statistics counters including those supported in BIND 8.
Faster ACL processing.
Efficient LRU cache-cleaning mechanism.
NSID support.
the patch from ISC for lib/bind9/check.c and deletion of unused
files in lib/bind.
This version will by default randomize the UDP query source port
(and sequence number of course) for every query.
In order to take advantage of this randomization users MUST have an
appropriate firewall configuration to allow UDP queries to be sent and
answers to be received on random ports; and users MUST NOT specify a
port number using the query-source[-v6] options.
The avoid-v[46]-udp-ports options exist for users who wish to eliminate
certain port numbers from being chosen by named for this purpose. See
the ARM Chatper 6 for more information.
Also please note, this issue applies only to UDP query ports. A random
ephemeral port is always chosen for TCP queries.
This issue applies primarily to name servers whose main purpose is to
resolve random queries (sometimes referred to as "caching" servers, or
more properly as "resolving" servers), although even an "authoritative"
name server will make some queries, primarily at startup time.
All users of BIND are strongly encouraged to upgrade to the latest
version, and to utilize the source port randomization feature.
This update addresses issues raised in:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-1447http://www.kb.cert.org/vuls/id/800113http://tools.ietf.org/html/draft-ietf-dnsext-forgery-resilience
1. The default access control lists (acls) are not being
correctly set. If not set anyone can make recursive queries
and/or query the cache contents.
See also:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-2925
2. The DNS query id generation is vulnerable to cryptographic
analysis which provides a 1 in 8 chance of guessing the next
query id for 50% of the query ids. This can be used to perform
cache poisoning by an attacker.
This bug only affects outgoing queries, generated by BIND 9 to
answer questions as a resolver, or when it is looking up data
for internal uses, such as when sending NOTIFYs to slave name
servers.
All users are encouraged to upgrade.
See also:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-2926
Approved by: re (kensmith, implicit)
announced by ISC dated 31 October (delivered via e-mail to the
bind-announce@isc.org list on 2 November):
Description:
Because of OpenSSL's recently announced vulnerabilities
(CAN-2006-4339, CVE-2006-2937 and CVE-2006-2940) which affect named,
we are announcing this workaround and releasing patches. A proof of
concept attack on OpenSSL has been demonstrated for CAN-2006-4339.
OpenSSL is required to use DNSSEC with BIND.
Fix for version 9.3.2-P1 and lower:
Upgrade to BIND 9.3.2-P2, then generate new RSASHA1 and
RSAMD5 keys for all old keys using the old default exponent
and perform a key rollover to these new keys.
These versions also change the default RSA exponent to be
65537 which is not vulnerable to the attacks described in
CAN-2006-4339.
