Important CentOS qemu-kvm Update


qemu-guest-agent-, qemu-img-, qemu-kvm-, qemu-kvm-, qemu-kvm-tools-,
2018-01-18 11:04
2017-07-27 19:04
2017-04-01 19:06
2017-01-05 20:10


Updated qemu-kvm packages that fix one security issue 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.

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

* 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.

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

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.
Please see

Am I vulnerable?

The constraints below list the versions that this vulnerability is patched in, and versions that are unaffected. If a patch is ready but unrealeased, then it is pending.

Or, you can just let us figure it out for you! Appcanary continously monitor your installed packages, and tell you if any of them are vulnerable.

Sign up for monitoring

Affected package information

Release Package Patched in
6 qemu-guest-agent qemu-guest-agent-
qemu-img qemu-img-
qemu-kvm qemu-kvm-
qemu-kvm qemu-kvm-
qemu-kvm-tools qemu-kvm-tools-