RHSA-2008:0300 - Security Advisory

Topic

Updated bind packages that fix two security issues, several bugs, and add
enhancements are now available for Red Hat Enterprise Linux 5.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

Description

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain
Name System (DNS) protocols. BIND includes a DNS server (named); a resolver
library (routines for applications to use when interfacing with DNS); and
tools for verifying that the DNS server is operating correctly.

It was discovered that the bind packages created the "rndc.key" file with
insecure file permissions. This allowed any local user to read the content
of this file. A local user could use this flaw to control some aspects of
the named daemon by using the rndc utility, for example, stopping the named
daemon. This problem did not affect systems with the bind-chroot package
installed. (CVE-2007-6283)

A buffer overflow flaw was discovered in the "inet_network()" function, as
implemented by libbind. An attacker could use this flaw to crash an
application calling this function, with an argument provided from an
untrusted source. (CVE-2008-0122)

As well, these updated packages fix the following bugs:

• when using an LDAP backend, missing function declarations caused

segmentation faults, due to stripped pointers on machines where pointers
are longer than integers.

• starting named may have resulted in named crashing, due to a race

condition during D-BUS connection initialization. This has been resolved in
these updated packages.

• the named init script returned incorrect error codes, causing the

"status" command to return an incorrect status. In these updated packages,
the named init script is Linux Standard Base (LSB) compliant.

• in these updated packages, the "rndc [command] [zone]" command, where

[command] is an rndc command, and [zone] is the specified zone, will find
the [zone] if the zone is unique to all views.

• the default named log rotation script did not work correctly when using

the bind-chroot package. In these updated packages, installing
bind-chroot creates the symbolic link "/var/log/named.log", which points
to "/var/named/chroot/var/log/named.log", which resolves this issue.

• a previous bind update incorrectly changed the permissions on the

"/etc/openldap/schema/dnszone.schema" file to mode 640, instead of mode
644, which resulted in OpenLDAP not being able to start. In these updated
packages, the permissions are correctly set to mode 644.

• the "checkconfig" parameter was missing in the named usage report. For

example, running the "service named" command did not return "checkconfig"
in the list of available options.

• due to a bug in the named init script not handling the rndc return value

correctly, the "service named stop" and "service named restart" commands
failed on certain systems.

• the bind-chroot spec file printed errors when running the "%pre" and

"%post" sections. Errors such as the following occurred:

Locating //etc/named.conf failed:
[FAILED]

This has been resolved in these updated packages.

• installing the bind-chroot package creates a "/dev/random" file in the

chroot environment; however, the "/dev/random" file had an incorrect
SELinux label. Starting named resulted in an 'avc: denied { getattr } for
pid=[pid] comm="named" path="/dev/random"' error being logged. The
"/dev/random" file has the correct SELinux label in these updated packages.

• in certain situations, running the "bind +trace" command resulted in

random segmentation faults.

As well, these updated packages add the following enhancements:

• support has been added for GSS-TSIG (RFC 3645).
• the "named.root" file has been updated to reflect the new address for

L.ROOT-SERVERS.NET.

• updates BIND to the latest 9.3 maintenance release.

All users of bind are advised to upgrade to these updated packages, which
resolve these issues and add these enhancements.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/FAQ_58_10188

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 240788 - bind_sdb, ldap2zone segfaulting
• BZ - 240876 - bind crashes on restart and also when running without forwarders
• BZ - 242734 - Wrong init script
• BZ - 247486 - bind-chroot does not modify /etc/logrotate.d/named
• BZ - 250118 - dnszone.schema bad file permissions
• BZ - 250744 - missed parameter "configtest" in init script usage report
• BZ - 250901 - "service named restart" fails
• BZ - 251528 - RFE: add support for GSSTSIG
• BZ - 252334 - bind-chroot-9.3.3-9.0.1 leaks error noise in its scripts
• BZ - 253537 - avc: denied { getattr } for comm="named" path="/dev/random"
• BZ - 353741 - Rebase to latest 9.3 maintenance release
• BZ - 363531 - New L.ROOT-SERVERS.NET address
• BZ - 419421 - CVE-2007-6283 bind: /etc/rndc.key has 644 permissions by default
• BZ - 423741 - resolver library causes segfaults in bind-utils such as dig,ping
• BZ - 429149 - CVE-2008-0122 libbind off-by-one buffer overflow

CVEs

• CVE-2008-0122
• CVE-2007-6283

References

• http://www.redhat.com/security/updates/classification/#moderate