RHSA-2011:1777

Problem Description:

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.

2. Relevant releases/architectures:

Red Hat Enterprise Linux Desktop (v. 6) - x86_64
Red Hat Enterprise Linux HPC Node (v. 6) - x86_64
Red Hat Enterprise Linux Server (v. 6) - x86_64
Red Hat Enterprise Linux Workstation (v. 6) - x86_64

3. 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-kvm handled VSC_ATR messages when a guest
was configured for a CCID (Chip/Smart Card Interface Devices) USB smart
card reader in passthrough mode. An attacker able to connect to the port on
the host being used for such a device could use this flaw to crash the
qemu-kvm process on the host or, possibly, escalate their privileges on the
host. (CVE-2011-4111)

All users of qemu-kvm should upgrade to these updated packages, which
contain a backported patch to 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.

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/kb/docs/DOC-11259

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

751310 - CVE-2011-4111 qemu: ccid: buffer overflow in handling of VSC_ATR message