RHSA-2015:0980 - Security Advisory

Topic

Updated pcs packages that fix one security issue and one bug are now
available for Red Hat Enterprise Linux 7.

Red Hat Product Security 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

The pcs packages provide a command-line tool and a web UI to configure and
manage the Pacemaker and Corosync tools.

It was found that the pcs daemon did not sign cookies containing session
data that were sent to clients connecting via the pcsd web UI. A remote
attacker could use this flaw to forge cookies and bypass authorization
checks, possibly gaining elevated privileges in the pcsd web UI.
(CVE-2015-1848)

This issue was discovered by Tomas Jelinek of Red Hat.

This update also fixes the following bug:

• Previously, the Corosync tool allowed the two_node option and the

auto_tie_breaker option to exist in the corosync.conf file at the same
time. As a consequence, if both options were included, auto_tie_breaker was
silently ignored and the two_node fence race decided which node would
survive in the event of a communication break. With this update, the pcs
daemon has been fixed so that it does not produce corosync.conf files with
both two_node and auto_tie_breaker included. In addition, if both two_node
and auto_tie_breaker are detected in corosync.conf, Corosync issues a
message at start-up and disables two_node mode. As a result,
auto_tie_breaker effectively overrides two_node mode if both options are
specified. (BZ#1205848)

All pcs users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. After installing the
updated packages, the pcsd daemon will be restarted automatically.

Solution

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

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux High Availability for x86_64 7 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.4 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.3 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.2 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support 7.1 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 7 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.4 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.3 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.2 x86_64
• Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support 7.1 x86_64
• Red Hat Enterprise Linux High Availability (for RHEL Server) from RHUI 7 x86_64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) from RHUI 7 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Update Services for SAP Solutions 7.7 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Update Services for SAP Solutions 7.6 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Update Services for SAP Solutions 7.4 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Update Services for SAP Solutions 7.3 x86_64
• Red Hat Enterprise Linux High Availability for x86_64 - Update Services for SAP Solutions 7.2 x86_64

Fixes

• BZ - 1208294 - CVE-2015-1848 pcs: improper web session variable signing

CVEs

• CVE-2015-1848
• CVE-2015-3983

References

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