Security Advisory Important: rhev-hypervisor6 security and bug fix update

Advisory: RHSA-2011:1850-1
Type: Security Advisory
Severity: Important
Issued on: 2011-12-22
Last updated on: 2011-12-22
Affected Products: Red Hat Enterprise Virtualization 3
CVEs ( CVE-2011-4127


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

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. (CVE-2011-4127)

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.


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

Updated packages

Red Hat Enterprise Virtualization 3

File outdated by:  RHEA-2016:1555
    MD5: 60d5e56d3778152650e17bf42e6b86a2
SHA-256: 8c3da24634e2659145276da74f88431c11b27170b424051d9ac3964b2460b8bf
File outdated by:  RHEA-2016:1555
    MD5: a7c789f1028a68211be3f70aba497649
SHA-256: f099e7c5a6fef63f3b3d210792c934703b594b9da43c3562d756bf97601bf262
File outdated by:  RHSA-2012:1375
    MD5: 17a144d7f02d175341ffa0d1100de98b
SHA-256: d5df1a1970b2d8152b5e231c23f3eff67b5517f237692f8b4e904cbe4c837a51
(The unlinked packages above are only available from the Red Hat Network)

Bugs fixed (see bugzilla for more information)

752375 - CVE-2011-4127 kernel: possible privilege escalation via SG_IO ioctl
760333 - rhev-hypervisor6 6.2 update 1 release bugzilla
761537 - vlan id should not accept a space in it
765898 - netconsole does not work


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