RHEL 6 : rhev-hypervisor6 (RHSA-2011:1850)

Medium Nessus Plugin ID 79281


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


An updated rhev-hypervisor6 package that fixes one security issue and two bugs is now available.

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.

The rhev-hypervisor6 package provides a Red Hat Enterprise Virtualization Hypervisor ISO disk image. The Red Hat Enterprise Virtualization Hypervisor is a dedicated Kernel-based Virtual Machine (KVM) hypervisor. It includes everything necessary to run and manage virtual machines: A subset of the Red Hat Enterprise Linux operating environment and the Red Hat Enterprise Virtualization Agent.

Note: Red Hat Enterprise Virtualization Hypervisor is only available for the Intel 64 and AMD64 architectures with virtualization extensions.

Using the SG_IO IOCTL to issue SCSI requests to partitions or LVM volumes resulted in the requests being passed to the underlying block device. If a privileged user only had access to a single partition or LVM volume, they could use this flaw to bypass those restrictions and gain read and write access (and be able to issue other SCSI commands) to the entire block device.

In KVM (Kernel-based Virtual Machine) environments using raw format virtio disks backed by a partition or LVM volume, a privileged guest user could bypass intended restrictions and issue read and write requests (and other SCSI commands) on the host, and possibly access the data of other guests that reside on the same underlying block device. Refer to Red Hat Bugzilla bug 752375 for further details and a mitigation script for users who cannot apply this update immediately.

This updated package provides updated components that include fixes for various security issues. These issues have no security impact on Red Hat Enterprise Virtualization Hypervisor itself, however. The security fixes included in this update address the following CVE numbers :

CVE-2011-4539 (dhcp issue)

CVE-2011-4339 (ipmitool issue)

CVE-2011-1530 (krb5 issue)

This update also fixes the following bugs :

* Virtual LAN (VLAN) identifiers containing a space were accepted, even though they could not be configured correctly. With this update, VLAN identifiers containing a space are rejected with an 'Invalid VLAN ID' message. (BZ#761537)

* After configuring netconsole, it was not possible to start the service: the 'service netconsole start' command failed with a warning that configfs.ko could not be found, and a fatal error that netconsole.ko could not be inserted. With this update, the netconsole service starts as expected. Note that after netconsole is configured, the service will not automatically start, even after rebooting. The service must be manually started. (BZ#765898)

Users of the Red Hat Enterprise Virtualization Hypervisor are advised to upgrade to this updated package, which corrects these issues.


Update the affected rhev-hypervisor6 and / or rhev-hypervisor6-tools packages.

See Also




Plugin Details

Severity: Medium

ID: 79281

File Name: redhat-RHSA-2011-1850.nasl

Version: $Revision: 1.2 $

Type: local

Agent: unix

Published: 2014/11/17

Modified: 2017/01/04

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 4.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:rhev-hypervisor6, p-cpe:/a:redhat:enterprise_linux:rhev-hypervisor6-tools, cpe:/o:redhat:enterprise_linux:6

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

Patch Publication Date: 2011/12/22

Reference Information

CVE: CVE-2011-4127

RHSA: 2011:1850