RHSA-2012:1131 - Security Advisory

Topic

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

The Red Hat Security Response Team has rated this update as having
important 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).

An uninitialized pointer use flaw was found in the way the MIT Kerberos KDC
handled initial authentication requests (AS-REQ). A remote,
unauthenticated attacker could use this flaw to crash the KDC via a
specially-crafted AS-REQ request. (CVE-2012-1015)

A NULL pointer dereference flaw was found in the MIT Kerberos
administration daemon, kadmind. A Kerberos administrator who has the
"create" privilege could use this flaw to crash kadmind. (CVE-2012-1013)

Red Hat would like to thank the MIT Kerberos project for reporting
CVE-2012-1015. Upstream acknowledges Emmanuel Bouillon (NCI Agency) as the
original reporter of CVE-2012-1015.

All krb5 users should upgrade to these updated packages, which contain
backported patches to correct these issues. After installing the updated
packages, the krb5kdc and kadmind daemons 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/knowledge/articles/11258

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 6.3 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.3 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 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 6.3 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.3 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 6.3 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.3 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 827517 - CVE-2012-1013 krb5: kadmind denial of service
• BZ - 838012 - CVE-2012-1015 krb5: KDC daemon crash via free() of an uninitialized pointer

CVEs

• CVE-2012-1013
• CVE-2012-1015

References

• https://access.redhat.com/security/updates/classification/#important
• http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2012-001.txt