CentOS Errata and Security Advisory CESA-2012:0683
The dynamic LDAP back end is a plug-in for BIND that provides back-end capabilities to LDAP databases. It features support for dynamic updates and internal caching that help to reduce the load on LDAP servers.
A flaw was found in the way bind-dyndb-ldap handled LDAP query errors. If a remote attacker were able to send DNS queries to a named server that is configured to use bind-dyndb-ldap, they could trigger such an error with a DNS query leveraging bind-dyndb-ldap's insufficient escaping of the LDAP base DN (distinguished name). This would result in an invalid LDAP query that named would retry in a loop, preventing it from responding to other DNS queries. With this update, bind-dyndb-ldap only attempts to retry one time when an LDAP search returns an unexpected error. (CVE-2012-2134)
Red Hat would like to thank Ronald van Zantvoort for reporting this issue.
All bind-dyndb-ldap users should upgrade to this updated package, which contains a backported patch to correct this issue. For the update to take effect, the named service must be restarted.
Merged security bulletin from advisories: http://lists.centos.org/pipermail/centos-announce/2012-May/030690.html
Affected packages: bind-dyndb-ldap
Upstream details at: https://rhn.redhat.com/errata/RHSA-2012-0683.html