RHSA-2015:1925 - Security Advisory

Topic

Updated kvm packages that fix one security issue are now available for Red
Hat Enterprise Linux 5.

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.

A heap buffer overflow flaw was found in the way QEMU's NE2000 NIC
emulation implementation handled certain packets received over the network.
A privileged user inside a guest could use this flaw to crash the QEMU
instance (denial of service) or potentially execute arbitrary code on
the host. (CVE-2015-5279)

Red Hat would like to thank Qinghao Tang of QIHU 360 Inc. for reporting
this issue.

All kvm users are advised to upgrade to these updated packages, which
contain a backported patch to correct this issue. Note: The procedure in
the Solution section must be performed before this update will 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

The following procedure must be performed before this update will take
effect:

1) Stop all KVM guest virtual machines.

2) Either reboot the hypervisor machine or, as the root user, remove (using
"modprobe -r [module]") and reload (using "modprobe [module]") all of the
following modules which are currently running (determined using "lsmod"):
kvm, ksm, kvm-intel or kvm-amd.

3) Restart the KVM guest virtual machines.

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Workstation 5 x86_64

Fixes

• BZ - 1256672 - CVE-2015-5279 qemu: Heap overflow vulnerability in ne2000_receive() function

CVEs

• CVE-2015-5279

References

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