RHEL 6 : qemu-kvm (RHSA-2011:0919)

high Nessus Plugin ID 63987

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Synopsis

The remote Red Hat host is missing one or more security updates.

Description

Updated qemu-kvm packages that fix two security issues and one bug are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links 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.

It was found that the virtio subsystem in qemu-kvm did not properly validate virtqueue in and out requests from the guest. A privileged guest user could use this flaw to trigger a buffer overflow, allowing them to crash the guest (denial of service) or, possibly, escalate their privileges on the host. (CVE-2011-2212)

It was found that the virtio_queue_notify() function in qemu-kvm did not perform sufficient input validation on the value later used as an index into the array of virtqueues. An unprivileged guest user could use this flaw to crash the guest (denial of service) or, possibly, escalate their privileges on the host. (CVE-2011-2512)

Red Hat would like to thank Nelson Elhage for reporting CVE-2011-2212.

This update also fixes the following bug :

* A bug was found in the way vhost (in qemu-kvm) set up mappings with the host kernel's vhost module. This could result in the host kernel's vhost module not having a complete view of a guest system's memory, if that guest had more than 4 GB of memory. Consequently, hot plugging a vhost-net network device and restarting the guest may have resulted in that device no longer working. (BZ#701771)

All users of qemu-kvm should upgrade to these updated packages, which contain backported patches to resolve these issues. 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

Update the affected packages.

Plugin Details

Severity: High

ID: 63987

File Name: redhat-RHSA-2011-0919.nasl

Version: 1.14

Type: local

Agent: unix

Family: Red Hat Local Security Checks

Published: 1/24/2013

Updated: 1/14/2021

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.4

Vector: CVSS2#AV:A/AC:M/Au:S/C:C/I:C/A:C

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:6, p-cpe:/a:redhat:enterprise_linux:qemu-img, p-cpe:/a:redhat:enterprise_linux:qemu-kvm-tools, p-cpe:/a:redhat:enterprise_linux:qemu-kvm, p-cpe:/a:redhat:enterprise_linux:qemu-kvm-debuginfo, cpe:/o:redhat:enterprise_linux:6.1

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Patch Publication Date: 7/5/2011

Vulnerability Publication Date: 6/21/2012

Reference Information

CVE: CVE-2011-2212, CVE-2011-2512

RHSA: 2011:0919

Detections

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