Scientific Linux Security Update : qemu-kvm on SL6.x x86_64

This script is Copyright (C) 2012 Tenable Network Security, Inc.


Synopsis :

The remote Scientific Linux host is missing one or more security
updates.

Description :

KVM (Kernel-based Virtual Machine) is a full virtualization solution
for Linux on AMD64 and Intel 64 systems. qemu-kvm is 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)

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.

All users of qemu-kvm should upgrade to these updated packages, which
resolve this issue. 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.

To resolve dependency issues, the usbredir packages have been added to
the repos.

See also :

http://www.nessus.org/u?0044811e

Solution :

Update the affected packages.

Risk factor :

High / CVSS Base Score : 7.2
(CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C)

Family: Scientific Linux Local Security Checks

Nessus Plugin ID: 61795 ()

Bugtraq ID:

CVE ID: CVE-2012-3515