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

Advisory: RHSA-2010:0172-1
Type: Security Advisory
Severity: Important
Issued on: 2010-03-24
Last updated on: 2010-03-24
Affected Products: Red Hat Enterprise Virtualization
CVEs ( CVE-2009-3722


An updated rhev-hypervisor package that fixes multiple security issues and
several bugs is now available.

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.

The rhev-hypervisor package provides a Red Hat Enterprise Virtualization
(RHEV) Hypervisor ISO disk image. The RHEV 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: RHEV Hypervisor is only available for the Intel 64 and AMD64
architectures with virtualization extensions.

A flaw was found in the sctp_rcv_ootb() function in the Linux kernel Stream
Control Transmission Protocol (SCTP) implementation. A remote attacker
could send a specially-crafted SCTP packet to a target system, resulting in
a denial of service. (CVE-2010-0008)

A flaw was found in the way the x86 emulator in KVM loaded segment
selectors (used for memory segmentation and protection) into segment
registers. In some guest system configurations, an unprivileged guest user
could leverage this flaw to crash the guest or possibly escalate their
privileges within the guest. (CVE-2010-0419)

The KVM x86 emulator implementation was missing a check for the Current
Privilege Level (CPL) while accessing debug registers. An unprivileged user
in a guest could leverage this flaw to crash the guest. (CVE-2009-3722)

A flaw was found in the USB passthrough handling code in KVM. A
specially-crafted USB packet sent from inside a guest could be used to
trigger a buffer overflow in the usb_host_handle_control() function, which
runs under the QEMU-KVM context on the host. A user in a guest could
leverage this flaw to cause a denial of service (guest hang or crash) or
possibly escalate their privileges within the host. (CVE-2010-0297)

This updated package provides updated components that include fixes for
security issues; however, these issues have no security impact for RHEV
Hypervisor. These fixes are for kernel issues CVE-2009-4308, CVE-2010-0003,
CVE-2010-0007, CVE-2010-0415, and CVE-2010-0437; and sudo issues
CVE-2010-0426 and CVE-2010-0427.

This update also fixes the following bugs:

* the required storage device driver was not detected correctly by mkdumprd
when using multipath devices. When RHEV Hypervisor was installed on a
multipath device, kdump was unable to mount the logical volume to store the
kernel core dump; therefore, the core dump would not be recorded. With this
update, multipath support has been added to the mkdumprd tool, which
resolves this issue. (BZ#569459)

As RHEV Hypervisor is based on KVM, the bug fixes from KVM updates
RHSA-2010:0126 and RHBA-2010:0158 have been included in this update:

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

(The unlinked packages above are only available from the Red Hat Network)

Bugs fixed (see bugzilla for more information)

531660 - CVE-2009-3722 KVM: Check cpl before emulating debug register access
555658 - CVE-2010-0008 kernel: sctp remote denial of service
557025 - CVE-2010-0297 kvm-userspace-rhel5: usb-linux.c: fix buffer overflow
563463 - CVE-2010-0419 kvm: emulator privilege escalation segment selector check


These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from:

The Red Hat security contact is More contact details at