what you don't know can hurt you

Red Hat Security Advisory 2012-1233-01

Red Hat Security Advisory 2012-1233-01
Posted Sep 5, 2012
Authored by Red Hat | Site access.redhat.com

Red Hat Security Advisory 2012-1233-01 - KVM is a full virtualization solution for Linux on AMD64 and Intel 64 systems. The qemu-kvm-rhev packages form the user-space component for running virtual machines using KVM. 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-kvm process on the host or, possibly, escalate their privileges on the host. When using qemu-kvm-rhev on a Red Hat Enterprise Linux 6 host not managed by Red Hat Enterprise Virtualization:

tags | advisory
systems | linux, redhat
advisories | CVE-2012-3515
MD5 | 6ae66993967f64b6d11d8246f44644fb

Red Hat Security Advisory 2012-1233-01

Change Mirror Download
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

=====================================================================
Red Hat Security Advisory

Synopsis: Important: qemu-kvm-rhev security and bug fix update
Advisory ID: RHSA-2012:1233-01
Product: Red Hat Enterprise Virtualization
Advisory URL: https://rhn.redhat.com/errata/RHSA-2012-1233.html
Issue date: 2012-09-05
CVE Names: CVE-2012-3515
=====================================================================

1. Summary:

Updated qemu-kvm-rhev packages that fix one security issue and two 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. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from the
CVE link in the References section.

2. Relevant releases/architectures:

RHEV Agents (vdsm) - x86_64

3. Description:

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. The qemu-kvm-rhev packages form the
user-space component for running virtual machines using KVM.

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-kvm process on the
host or, possibly, escalate their privileges on the host. (CVE-2012-3515)

When using qemu-kvm-rhev on a Red Hat Enterprise Linux 6 host not managed
by Red Hat Enterprise Virtualization:

* This flaw did not affect the default use of KVM. Affected configurations
were:

- - When guests were started from the command line ("/usr/libexec/qemu-kvm")
without the "-nodefaults" option, and also without specifying a
serial or parallel device, or a virtio-console device, that specifically
does not use a virtual console (vc) back-end. (Note that Red Hat does not
support invoking "qemu-kvm" from the command line without "-nodefaults" on
Red Hat Enterprise Linux 6.)

- - Guests that were managed via libvirt, such as when using Virtual Machine
Manager (virt-manager), but that have a serial or parallel device, or a
virtio-console device, that uses a virtual console back-end. By default,
guests managed via libvirt will not use a virtual console back-end for such
devices.

When using qemu-kvm-rhev on a Red Hat Enterprise Virtualization managed Red
Hat Enterprise Linux 6 host:

* This flaw did not affect the default use of a Red Hat Enterprise
Virtualization host: it is not possible to add a device that uses a virtual
console back-end via Red Hat Enterprise Virtualization Manager.

To specify a virtual console back-end for a device and therefore be
vulnerable to this issue, the device would have to be created another way,
for example, by using a VDSM hook.

Red Hat would like to thank the Xen project for reporting this issue.

This update also fixes the following bugs:

* Previously, the KVM modules were not loaded by the postinstall scriptlet
of RPM scripts. This bug caused various issues and required the system to
be rebooted to resolve them. With this update, the modules are loaded
properly by the scriptlet and no unnecessary reboots are now required.
(BZ#839897)

* Previously, when a guest was started up with two serial devices, qemu-kvm
returned an error message and terminated the boot because IRQ 4 for the ISA
bus was being used by both devices. This update fixes the qemu-kvm code,
which allows IRQ 4 to be used by more than one device on the ISA bus, and
the boot now succeeds in the described scenario. (BZ#840054)

All users of qemu-kvm-rhev are advised to upgrade to these updated
packages, which fix these issues. After installing this update, shut down
all running virtual machines. Once all virtual machines have shut down,
start them again for this update to take effect.

4. 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

5. Bugs fixed (http://bugzilla.redhat.com/):

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

6. Package List:

RHEV Agents (vdsm):

Source:
ftp://ftp.redhat.com/pub/redhat/linux/enterprise/6Server/en/RHEV/SRPMS/qemu-kvm-rhev-0.12.1.2-2.295.el6_3.2.src.rpm

x86_64:
qemu-img-rhev-0.12.1.2-2.295.el6_3.2.x86_64.rpm
qemu-kvm-rhev-0.12.1.2-2.295.el6_3.2.x86_64.rpm
qemu-kvm-rhev-debuginfo-0.12.1.2-2.295.el6_3.2.x86_64.rpm
qemu-kvm-rhev-tools-0.12.1.2-2.295.el6_3.2.x86_64.rpm

These packages are GPG signed by Red Hat for security. Our key and
details on how to verify the signature are available from
https://access.redhat.com/security/team/key/#package

7. References:

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

8. Contact:

The Red Hat security contact is <secalert@redhat.com>. More contact
details at https://access.redhat.com/security/team/contact/

Copyright 2012 Red Hat, Inc.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.4 (GNU/Linux)

iD8DBQFQR4YVXlSAg2UNWIIRAq5WAJ9Z18R5/JvEpbbnZm47gi4lcxRSpACdHlZA
BcVS3dd+MxlwoYjMQtUCINU=
=3sF2
-----END PGP SIGNATURE-----


--
RHSA-announce mailing list
RHSA-announce@redhat.com
https://www.redhat.com/mailman/listinfo/rhsa-announce

Comments

RSS Feed Subscribe to this comment feed

No comments yet, be the first!

Login or Register to post a comment

File Archive:

November 2019

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Nov 1st
    28 Files
  • 2
    Nov 2nd
    1 Files
  • 3
    Nov 3rd
    1 Files
  • 4
    Nov 4th
    12 Files
  • 5
    Nov 5th
    19 Files
  • 6
    Nov 6th
    65 Files
  • 7
    Nov 7th
    22 Files
  • 8
    Nov 8th
    18 Files
  • 9
    Nov 9th
    1 Files
  • 10
    Nov 10th
    1 Files
  • 11
    Nov 11th
    11 Files
  • 12
    Nov 12th
    65 Files
  • 13
    Nov 13th
    0 Files
  • 14
    Nov 14th
    0 Files
  • 15
    Nov 15th
    0 Files
  • 16
    Nov 16th
    0 Files
  • 17
    Nov 17th
    0 Files
  • 18
    Nov 18th
    0 Files
  • 19
    Nov 19th
    0 Files
  • 20
    Nov 20th
    0 Files
  • 21
    Nov 21st
    0 Files
  • 22
    Nov 22nd
    0 Files
  • 23
    Nov 23rd
    0 Files
  • 24
    Nov 24th
    0 Files
  • 25
    Nov 25th
    0 Files
  • 26
    Nov 26th
    0 Files
  • 27
    Nov 27th
    0 Files
  • 28
    Nov 28th
    0 Files
  • 29
    Nov 29th
    0 Files
  • 30
    Nov 30th
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2019 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close