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Alerts This Week
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RedHat: RHSA-2016-0004-01 Critical Kernel Denial of Service Vulnerability

red hat
Calendar Grey January 7, 2016
Scroller Redhat
The latest kernel release from Red Hat tackles several critical vulnerabilities by implementing fortified defenses and targeted fixes.
Updated kernel packages that fix two security issues are now available for Red Hat Enterprise Linux 6.4 Advanced Update Support

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

Summary

The kernel packages contain the Linux kernel, the core of any Linux operating system.
* It was found that the x86 ISA (Instruction Set Architecture) is prone to a denial of service attack inside a virtualized environment in the form of an infinite loop in the microcode due to the way (sequential) delivering of benign exceptions such as #AC (alignment check exception) and #DB (debug exception) is handled. A privileged user inside a guest could use these flaws to create denial of service conditions on the host kernel. (CVE-2015-5307, CVE-2015-8104, Important)
Red Hat would like to thank Ben Serebrin of Google Inc. for reporting the CVE-2015-5307 issue.
All kernel users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. The system must be rebooted for this update to take effect.

Topics%20covered

Topics Covered

security advisory kernel update DoS Red Hat Enterprise Linux important issue

References

https://access.redhat.com/security/cve/CVE-2015-5307 https://access.redhat.com/security/cve/CVE-2015-8104 https://access.redhat.com/security/updates/classification#important

Package List

Red Hat Enterprise Linux Server AUS (v. 6.4):
Source: kernel-2.6.32-358.69.1.el6.src.rpm
i386: kernel-2.6.32-358.69.1.el6.i686.rpm kernel-debug-2.6.32-358.69.1.el6.i686.rpm kernel-debug-debuginfo-2.6.32-358.69.1.el6.i686.rpm kernel-debug-devel-2.6.32-358.69.1.el6.i686.rpm kernel-debuginfo-2.6.32-358.69.1.el6.i686.rpm kernel-debuginfo-common-i686-2.6.32-358.69.1.el6.i686.rpm kernel-devel-2.6.32-358.69.1.el6.i686.rpm kernel-headers-2.6.32-358.69.1.el6.i686.rpm perf-2.6.32-358.69.1.el6.i686.rpm perf-debuginfo-2.6.32-358.69.1.el6.i686.rpm python-perf-debuginfo-2.6.32-358.69.1.el6.i686.rpm
noarch: kernel-doc-2.6.32-358.69.1.el6.noarch.rpm kernel-firmware-2.6.32-358.69.1.el6.noarch.rpm
ppc64: kernel-2.6.32-358.69.1.el6.ppc64.rpm kernel-bootwrapper-2.6.32-358.69.1.el6.ppc64.rpm kernel-debug-2.6.32-358.69.1.el6.ppc64.rpm kernel-debug-debuginfo-2.6.32-358.69.1.el6.ppc64.rpm kernel-debug-devel-2.6.32-358.69.1.el6.ppc64.rpm kernel-debuginfo-2.6.32-358.69.1.el6.ppc64.rpm kernel-debuginfo-common-ppc64-2.6.32-358.69.1.el6.ppc64.rpm kernel-devel-2.6.32-358.69.1.el6.ppc64.rpm kernel-headers-2.6.32-358.69.1.el6.ppc64.rpm perf-2.6.32-358.69.1.el6.ppc64.rpm perf-debuginfo-2.6.32-358.69.1.el6.ppc64.rpm python-perf-debuginfo-2.6.32-358.69.1.el6.ppc64.rpm
s390x:

Read the Full Advisory


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2016:0004-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2016:0004.html
Issue date: 2016-01-07

Topic

Updated kernel packages that fix two security issues are now available forRed Hat Enterprise Linux 6.4 Advanced Update Support.Red Hat Product Security has rated this update as having Important securityimpact. Common Vulnerability Scoring System (CVSS) base scores, which givedetailed severity ratings, are available for each vulnerability from theCVE links in the References section.

Topics%20covered

Topics Covered

security advisory kernel update DoS Red Hat Enterprise Linux important issue

Relevant Releases Architectures

Red Hat Enterprise Linux Server AUS (v. 6.4) - i386, noarch, ppc64, s390x, x86_64

Red Hat Enterprise Linux Server Optional AUS (v. 6.4) - i386, ppc64, s390x, x86_64

Bugs Fixed

1277172 - CVE-2015-5307 virt: guest to host DoS by triggering an infinite loop in microcode via #AC exception

1278496 - CVE-2015-8104 virt: guest to host DoS by triggering an infinite loop in microcode via #DB exception

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