RHSA-2013:0189 - Security Advisory

Topic

An updated ipa-client package that fixes one security issue is now
available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having
important security impact. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from the
CVE link in the References section.

Description

Red Hat Identity Management is a centralized authentication, identity
management and authorization solution for both traditional and cloud-based
enterprise environments.

A weakness was found in the way IPA clients communicated with IPA servers
when initially attempting to join IPA domains. As there was no secure way
to provide the IPA server's Certificate Authority (CA) certificate to the
client during a join, the IPA client enrollment process was susceptible to
man-in-the-middle attacks. This flaw could allow an attacker to obtain
access to the IPA server using the credentials provided by an IPA client,
including administrative access to the entire domain if the join was
performed using an administrator's credentials. (CVE-2012-5484)

Note: This weakness was only exposed during the initial client join to the
realm, because the IPA client did not yet have the CA certificate of the
server. Once an IPA client has joined the realm and has obtained the CA
certificate of the IPA server, all further communication is secure. If a
client were using the OTP (one-time password) method to join to the realm,
an attacker could only obtain unprivileged access to the server (enough to
only join the realm).

Red Hat would like to thank Petr Mensik for reporting this issue.

When a fix for this flaw has been applied to the client but not yet the
server, ipa-client-install, in unattended mode, will fail if you do not
have the correct CA certificate locally, noting that you must use the
"--force" option to insecurely obtain the certificate. In interactive mode,
the certificate will try to be obtained securely from LDAP. If this fails,
you will be prompted to insecurely download the certificate via HTTP. In
the same situation when using OTP, LDAP will not be queried and you will be
prompted to insecurely download the certificate via HTTP.

Users of ipa-client are advised to upgrade to this updated package, which
corrects this issue.

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 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.9 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.9 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.9 i386
• Red Hat Enterprise Linux Server - AUS 5.9 ia64
• 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 IBM z Systems - Extended Update Support 5.9 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.9 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386
• Red Hat Enterprise Linux Server - AUS 5.9 x86_64
• Red Hat Enterprise Linux Server - AUS 5.9 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.9 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.9 i386

Fixes

• BZ - 876307 - CVE-2012-5484 ipa: weakness when initiating join from IPA client can potentially compromise IPA domain

CVEs

• CVE-2012-5484

References

• https://access.redhat.com/security/updates/classification/#important