Synopsis

Important: rhev-hypervisor security and bug fix update

Type/Severity

Security Advisory: Important

Topic

An updated rhev-hypervisor package that fixes two 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.

Description

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.

It was discovered that OpenSSL did not always check the return value of
the bn_wexpand() function. An attacker able to trigger a memory allocation
failure in that function could cause an application using the OpenSSL
library to crash or, possibly, execute arbitrary code. (CVE-2009-3245)

A flaw was found in the way the TLS/SSL (Transport Layer Security/Secure
Sockets Layer) protocols handled session renegotiation. A man-in-the-middle
attacker could use this flaw to prefix arbitrary plain text to a client's
session (for example, an HTTPS connection to a website). This could force
the server to process an attacker's request as if authenticated using the
victim's credentials. This update addresses this flaw in openssl, nss, and
gnutls by implementing the TLS Renegotiation Indication Extension, as
defined in RFC 5746. (CVE-2009-3555)

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-2009-4307, CVE-2010-0727,
CVE-2009-4027, and CVE-2010-1188; cpio issues CVE-2010-0624 and
CVE-2007-4476; gnutls issue CVE-2009-2409; openssl issue CVE-2010-0433; and
tar issues CVE-2010-0624 and CVE-2007-4476.

This update also fixes the following bugs:

• bridged network interfaces using the bnx2x, mlx4_en, enic and s2io
  drivers had Large Receive Offload (LRO) enabled by default. This caused
  significantly degraded network I/O performance. LRO has been disabled for
  all network interface drivers which have LRO enabled by default in Red Hat
  Enterprise Linux 5. With this change, network I/O performance is
  significantly improved. (BZ#576374, BZ#579730)
  
• RHEV Hypervisor supported IPv6, but as this is not used to communicate
  with the RHEV Manager, it is superfluous. Support for IPv6 has now been
  disabled in RHEV Hypervisor. (BZ#577300)
  
• for VLAN interfaces, the hardware (MAC) address of the interface was set
  only in the VLAN ifcfg script, not in the physical interface ifcfg script.
  This caused network interfaces with VLAN tags to intermittently fail on
  boot. The MAC address is now set in the ifcfg script for the underlying
  physical interface. Network interfaces with VLAN tags now work consistently
  between reboots. (BZ#581876)
  
• the hypervisor would hang on reboot after repeated upgrade operations,
  due to GRUB accessing the /boot file system before it was flushed. The
  /boot file system is now remounted before GRUB accesses it. (BZ#591111)
  

As RHEV Hypervisor is based on KVM, the bug fixes from the KVM update
RHBA-2010:0434 have been included in this update. Also included are the bug
fixes from the RHEV Manager Agent (VDSM) update RHBA-2010:0435.

KVM: https://rhn.redhat.com/errata/RHBA-2010-0434.html
VDSM: https://rhn.redhat.com/errata/RHBA-2010-0435.html

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

Solution

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
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Virtualization 5 x86_64

Fixes

• BZ - 533125 - CVE-2009-3555 TLS: MITM attacks via session renegotiation
• BZ - 570924 - CVE-2009-3245 openssl: missing bn_wexpand return value checks

CVEs

• CVE-2009-3555
• CVE-2009-3245

References

• http://www.redhat.com/security/updates/classification/#important

This erratum does not contain any packages.