RHSA-2015:1837 - Security Advisory

Topic

Updated qemu-kvm-rhev packages that fix one security issue are now
available for Red Hat Enterprise Virtualization Hypervisor 7.

Red Hat Product Security 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.

Description

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

A heap-based buffer overflow issue was found in the QEMU emulator's VNC
display driver. It could occur while refreshing the VNC server's display
surface using the vnc_refresh_server_surface() routine. A privileged guest
user could use this flaw to corrupt the heap memory and crash the QEMU
process instance, or to potentially use it to execute arbitrary code on the
host. (CVE-2015-5225)

Red Hat would like to thank Mr Qinghao Tang from QIHU 360 Inc. and Mr
Zuozhi from Alibaba Inc. for reporting this issue.

All qemu-kvm-rhev users are advised to upgrade to these updated packages,
which contain a backported patch to correct 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.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Virtualization 3 for RHEL 7 x86_64

Fixes

• BZ - 1255896 - CVE-2015-5225 Qemu: ui: vnc: heap memory corruption in vnc_refresh_server_surface

CVEs

• CVE-2015-5225

References

• https://access.redhat.com/security/updates/classification/#important