Synopsis

Important: kernel security and bug fix update

Type/Severity

Security Advisory: Important

Topic

Updated kernel packages that fix multiple security issues and several bugs
are now available for Red Hat Enterprise Linux 6.

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 kernel packages contain the Linux kernel, the core of any Linux
operating system.

• A flaw was found in the way the get_rx_bufs() function in the vhost_net

implementation in the Linux kernel handled error conditions reported by the
vhost_get_vq_desc() function. A privileged guest user could use this flaw
to crash the host. (CVE-2014-0055, Important)

• A flaw was found in the way the Linux kernel processed an authenticated

COOKIE_ECHO chunk during the initialization of an SCTP connection. A remote
attacker could use this flaw to crash the system by initiating a specially
crafted SCTP handshake in order to trigger a NULL pointer dereference on
the system. (CVE-2014-0101, Important)

• A flaw was found in the way the Linux kernel's CIFS implementation

handled uncached write operations with specially crafted iovec structures.
An unprivileged local user with access to a CIFS share could use this flaw
to crash the system, leak kernel memory, or, potentially, escalate their
privileges on the system. Note: the default cache settings for CIFS mounts
on Red Hat Enterprise Linux 6 prohibit a successful exploitation of this
issue. (CVE-2014-0069, Moderate)

• A heap-based buffer overflow flaw was found in the Linux kernel's cdc-wdm

driver, used for USB CDC WCM device management. An attacker with physical
access to a system could use this flaw to cause a denial of service or,
potentially, escalate their privileges. (CVE-2013-1860, Low)

Red Hat would like to thank Nokia Siemens Networks for reporting
CVE-2014-0101, and Al Viro for reporting CVE-2014-0069.

This update also fixes several bugs. Documentation for these changes will
be available shortly from the Technical Notes document linked to in the
References section.

All kernel users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. The system must be
rebooted for this update to take effect.

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
https://access.redhat.com/site/articles/11258

To install kernel packages manually, use "rpm -ivh [package]". Do not use
"rpm -Uvh" as that will remove the running kernel binaries from your
system. You may use "rpm -e" to remove old kernels after determining that
the new kernel functions properly on your system.

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.5 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.5 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 i386
• Red Hat Enterprise Linux EUS Compute Node 6.5 x86_64
• Red Hat Enterprise Linux Server - AUS 6.5 x86_64
• Red Hat Enterprise Linux Server - TUS 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 921970 - CVE-2013-1860 kernel: usb: cdc-wdm buffer overflow triggered by device
• BZ - 1062577 - CVE-2014-0055 kernel: vhost-net: insufficient handling of error conditions in get_rx_bufs()
• BZ - 1064253 - CVE-2014-0069 kernel: cifs: incorrect handling of bogus user pointers during uncached writes
• BZ - 1070705 - CVE-2014-0101 kernel: net: sctp: null pointer dereference when processing authenticated cookie_echo chunk

CVEs

• CVE-2013-1860
• CVE-2014-0101
• CVE-2014-0055
• CVE-2014-0069
• CVE-2013-7266
• CVE-2013-7270
• CVE-2014-2038

References