Synopsis
Important: kernel security and bug fix update
Type/Severity
Security Advisory: Important
Topic
Updated kernel packages that fix two security issues and several bugs 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
The kernel packages contain the Linux kernel, the core of any Linux
operating system.
This update fixes the following security issues:
- A flaw was found in the way the xen_iret() function in the Linux kernel
used the DS (the CPU's Data Segment) register. A local, unprivileged user
in a 32-bit, para-virtualized Xen hypervisor guest could use this flaw to
crash the guest or, potentially, escalate their privileges. (CVE-2013-0228,
Important)
- A flaw was found in the way file permission checks for the
"/dev/cpu/[x]/msr" files were performed in restricted root environments
(for example, when using a capability-based security model). A local user
with the ability to write to these files could use this flaw to escalate
their privileges to kernel level, for example, by writing to the
SYSENTER_EIP_MSR register. (CVE-2013-0268, Important)
The CVE-2013-0228 issue was discovered by Andrew Jones of Red Hat.
This update also fixes several bugs. Documentation for these changes will
be available shortly from the Technical Notes document linked to in the
References section.
Users should upgrade to these updated packages, which contain backported
patches to correct these issues, and fix the bugs noted in the Technical
Notes. The system must be rebooted for this update to take effect.
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
To install kernel packages manually, use "rpm -ivh [package]". Do not
use "rpm -Uvh" as that will remove the running kernel binaries from
your system. You may use "rpm -e" to remove old kernels after
determining that the new kernel functions properly on your system.
Affected Products
-
Red Hat Enterprise Linux Server 6 x86_64
-
Red Hat Enterprise Linux Server 6 i386
-
Red Hat Enterprise Linux Server - Extended Update Support 6.4 x86_64
-
Red Hat Enterprise Linux Server - Extended Update Support 6.4 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 6.4 s390x
-
Red Hat Enterprise Linux for Power, big endian 6 ppc64
-
Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.4 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 6.4 x86_64
-
Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.4 i386
-
Red Hat Gluster Storage Server for On-premise 2.1 x86_64
-
Red Hat Storage for Public Cloud (via RHUI) 2.1 x86_64
-
Red Hat Enterprise Linux Server - AUS 6.4 x86_64
Fixes
- BZ - 906309 - CVE-2013-0228 kernel: xen: userspace alterable %ds access in xen_iret()
- BZ - 908693 - CVE-2013-0268 kernel: x86/msr: /dev/cpu/*/msr local privilege escalation
CVEs
References
Vulmon