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Red Hat Enterprise Linux: RHSA-2012:1236-01 Important Xen Emulation Issue

red hat
Calendar Grey September 5, 2012
Scroller Redhat
Critical xen security patch for Red Hat Enterprise Linux addresses virtualization vulnerability that could lead to unauthorized privilege escalation.
Updated xen packages that fix one security issue are now available for Red Hat Enterprise Linux 5

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

Summary

The xen packages contain administration tools and the xend service for managing the kernel-xen kernel for virtualization on Red Hat Enterprise Linux.
A flaw was found in the way QEMU handled VT100 terminal escape sequences when emulating certain character devices. A guest user with privileges to write to a character device that is emulated on the host using a virtual console back-end could use this flaw to crash the qemu process on the host or, possibly, escalate their privileges on the host. (CVE-2012-3515)
This flaw did not affect the default use of the Xen hypervisor implementation in Red Hat Enterprise Linux 5. This problem only affected fully-virtualized guests that have a serial or parallel device that uses a virtual console (vc) back-end. By default, the virtual console back-end is not used for such devices; only guests explicitly configured to use them in this way were affected.
Red Hat would like to thank the Xen project for reporting this issue.
All users of xen are advised to upgrade to these updated packages, which correct this issue. After installing the updated packages, all fully-virtualized guests must be restarted for this update to take effect.

Topics%20covered

Topics Covered

security advisory privilege escalation Red Hat Enterprise Linux important xen update emulation issue

References

https://access.redhat.com/security/cve/CVE-2012-3515 https://access.redhat.com/security/updates/classification/#important

Package List

Red Hat Enterprise Linux Desktop (v. 5 client):
Source:
i386: xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-libs-3.0.3-135.el5_8.5.i386.rpm
x86_64: xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-debuginfo-3.0.3-135.el5_8.5.x86_64.rpm xen-libs-3.0.3-135.el5_8.5.i386.rpm xen-libs-3.0.3-135.el5_8.5.x86_64.rpm
RHEL Desktop Multi OS (v. 5 client):
Source:
i386: xen-3.0.3-135.el5_8.5.i386.rpm xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-devel-3.0.3-135.el5_8.5.i386.rpm
x86_64: xen-3.0.3-135.el5_8.5.x86_64.rpm xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-debuginfo-3.0.3-135.el5_8.5.x86_64.rpm xen-devel-3.0.3-135.el5_8.5.i386.rpm xen-devel-3.0.3-135.el5_8.5.x86_64.rpm
Red Hat Enterprise Linux (v. 5 server):
Source:
i386: xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-libs-3.0.3-135.el5_8.5.i386.rpm
ia64: xen-debuginfo-3.0.3-135.el5_8.5.ia64.rpm xen-libs-3.0.3-135.el5_8.5.ia64.rpm
x86_64: xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-debuginfo-3.0.3-135.el5_8.5.x86_64.rpm xen-libs-3.0.3-135.el5_8.5.i386.rpm xen-libs-3.0.3-135.el5_8.5.x86_64.rpm
RHEL Virtualization (v. 5 server):
Source:
i386: xen-3.0.3-135.el5_8.5.i386.rpm xen-debuginfo-3.0.3-135.el5_8.5.i386.rpm xen-devel-3.0.3-135.el5_8.5.i386.rpm
ia64: xen-3.0.3-135.el5_8.5.ia64.rpm xen-debuginfo-3.0.3-135.el5_8.5.ia64.rpm

Read the Full Advisory


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2012:1236-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2012:1236.html
Issue date: 2012-09-05

Topic

Updated xen packages that fix one security issue are now available forRed Hat Enterprise Linux 5.The Red Hat Security Response Team has rated this update as havingimportant security impact. A Common Vulnerability Scoring System (CVSS)base score, which gives a detailed severity rating, is available from theCVE link in the References section.

Topics%20covered

Topics Covered

security advisory privilege escalation Red Hat Enterprise Linux important xen update emulation issue

Relevant Releases Architectures

RHEL Desktop Multi OS (v. 5 client) - i386, x86_64

RHEL Virtualization (v. 5 server) - i386, ia64, x86_64

Red Hat Enterprise Linux (v. 5 server) - i386, ia64, x86_64

Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64

Bugs Fixed

851252 - CVE-2012-3515 qemu: VT100 emulation vulnerability

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