(RHSA-2016:0379) Important: rhev-hypervisor security, bug fix and enhancement update

The rhev-hypervisor 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.

A padding oracle flaw was found in the Secure Sockets Layer version
2.0 (SSLv2) protocol. An attacker could potentially use this flaw to
decrypt RSA-encrypted cipher text from a connection using a newer
SSL/TLS protocol version, allowing them to decrypt such connections.
This cross-protocol attack is publicly referred to as DROWN.
(CVE-2016-0800)

Note: This issue was addressed by disabling the SSLv2 protocol by
default when using the ‘SSLv23’ connection methods, and removing
support for weak SSLv2 cipher suites. For more information, refer to
the knowledge base article linked in the References section.

A flaw was found in the way malicious SSLv2 clients could negotiate
SSLv2 ciphers that have been disabled on the server. This could
result in weak SSLv2 ciphers being used for SSLv2 connections,
making them vulnerable to man-in-the-middle attacks. (CVE-2015-3197)

A side-channel attack was found that makes use of cache-bank
conflicts on the Intel Sandy-Bridge microarchitecture. An attacker
who has the ability to control code in a thread running on the same
hyper-threaded core as the victim’s thread that is performing
decryption, could use this flaw to recover RSA private keys.
(CVE-2016-0702)

A double-free flaw was found in the way OpenSSL parsed certain
malformed DSA (Digital Signature Algorithm) private keys. An
attacker could create specially crafted DSA private keys that, when
processed by an application compiled against OpenSSL, could cause
the application to crash. (CVE-2016-0705)

An integer overflow flaw, leading to a NULL pointer dereference or a
heap-based memory corruption, was found in the way some BIGNUM
functions of OpenSSL were implemented. Applications that use these
functions with large untrusted input could crash or, potentially,
execute arbitrary code. (CVE-2016-0797)

Red Hat would like to thank the OpenSSL project for reporting these
issues. Upstream acknowledges Nimrod Aviram and Sebastian Schinzel
as the original reporters of CVE-2016-0800 and CVE-2015-3197; Yuval
Yarom (University of Adelaide and NICTA), Daniel Genkin (Technion
and Tel Aviv University), Nadia Heninger (University of Pennsylvania)
as the original reporters of CVE-2016-0702; Adam Langley (Google/
BoringSSL) as the original reporter of CVE-2016-0705; and Guido
Vranken as the original reporter of CVE-2016-0797.

All openssl users are advised to upgrade to this updated package,
which contain backported patches to correct these issues. For the
update to take effect, all services linked to the OpenSSL library
must be restarted, or the system rebooted.

Changes to the rhev-hypervisor component:

• Previously, a race between services during boot prevented network
  configuration from upgrading correctly. The risk for the race has
  now been reduced significantly to allow the upgrade of the network
  configuration to complete correctly. (BZ#1194068)

• Previously, using the text user interface (TUI) to log in to the
  administrator account of Red Hat Enterprise Virtualization
  Hypervisor failed with a Python backtrace. This update makes the
  “six” module correctly importable under all circumstances, which
  ensures that logging in to Red Hat Enterprise Virtualization
  Hypervisor using TUI proceeds as expected. (BZ#1246836)