RHSA-2011:1379 - Security Advisory

Topic

Updated krb5 packages that fix multiple security issues are now available
for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

Description

Kerberos is a network authentication system which allows clients and
servers to authenticate to each other using symmetric encryption and a
trusted third-party, the Key Distribution Center (KDC).

Multiple NULL pointer dereference and assertion failure flaws were found
in the MIT Kerberos KDC when it was configured to use an LDAP (Lightweight
Directory Access Protocol) or Berkeley Database (Berkeley DB) back end. A
remote attacker could use these flaws to crash the KDC. (CVE-2011-1527,
CVE-2011-1528, CVE-2011-1529)

Red Hat would like to thank the MIT Kerberos project for reporting the
CVE-2011-1527 issue. Upstream acknowledges Andrej Ota as the original
reporter of CVE-2011-1527.

All krb5 users should upgrade to these updated packages, which contain a
backported patch to correct these issues. After installing the updated
packages, the krb5kdc daemon will be restarted automatically.

Solution

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

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/kb/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 i386
• Red Hat Virtual Storage Appliance (from RHUI) 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 737711 - CVE-2011-1527 CVE-2011-1528 CVE-2011-1529 krb5: KDC denial of service vulnerabilities (MITKRB5-SA-2011-006)

CVEs

• CVE-2011-1529
• CVE-2011-1528
• CVE-2011-1527

References

• https://access.redhat.com/security/updates/classification/#moderate
• http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2011-006.txt