USN-1216-1: Linux kernel (EC2) vulnerabilities

Publication date

26 September 2011

Overview

Multiple kernel flaws have been fixed.

Releases


Packages

Details

Dan Rosenberg discovered that multiple terminal ioctls did not correctly
initialize structure memory. A local attacker could exploit this to read
portions of kernel stack memory, leading to a loss of privacy.
(CVE-2010-4076, CVE-2010-4077)

Alex Shi and Eric Dumazet discovered that the network stack did not
correctly handle packet backlogs. A remote attacker could exploit this by
sending a large amount of network traffic to cause the system to run out of
memory, leading to a denial of service. (CVE-2010-4251, CVE-2010-4805)

It was discovered that the /proc filesystem did not correctly handle
permission changes when programs executed. A local attacker could hold open
files to examine details about programs running with higher privileges,
potentially increasing the chances of...

Dan Rosenberg discovered that multiple terminal ioctls did not correctly
initialize structure memory. A local attacker could exploit this to read
portions of kernel stack memory, leading to a loss of privacy.
(CVE-2010-4076, CVE-2010-4077)

Alex Shi and Eric Dumazet discovered that the network stack did not
correctly handle packet backlogs. A remote attacker could exploit this by
sending a large amount of network traffic to cause the system to run out of
memory, leading to a denial of service. (CVE-2010-4251, CVE-2010-4805)

It was discovered that the /proc filesystem did not correctly handle
permission changes when programs executed. A local attacker could hold open
files to examine details about programs running with higher privileges,
potentially increasing the chances of exploiting additional
vulnerabilities. (CVE-2011-1020)

Dan Rosenberg discovered that the X.25 Rose network stack did not correctly
handle certain fields. If a system was running with Rose enabled, a remote
attacker could send specially crafted traffic to gain root privileges.
(CVE-2011-1493)

Timo Warns discovered that the GUID partition parsing routines did not
correctly validate certain structures. A local attacker with physical
access could plug in a specially crafted block device to crash the system,
leading to a denial of service. (CVE-2011-1577)

It was discovered that CIFS incorrectly handled authentication. When a user
had a CIFS share mounted that required authentication, a local user could
mount the same share without knowing the correct password. (CVE-2011-1585)

It was discovered that the GRE protocol incorrectly handled netns
initialization. A remote attacker could send a packet while the ip_gre
module was loading, and crash the system, leading to a denial of service.
(CVE-2011-1767)

It was discovered that the IP/IP protocol incorrectly handled netns
initialization. A remote attacker could send a packet while the ipip module
was loading, and crash the system, leading to a denial of service.
(CVE-2011-1768)

Ben Hutchings reported a flaw in the kernel's handling of corrupt LDM
partitions. A local user could exploit this to cause a denial of service or
escalate privileges. (CVE-2011-2182)

Andrea Righi discovered a race condition in the KSM memory merging support.
If KSM was being used, a local attacker could exploit this to crash the
system, leading to a denial of service. (CVE-2011-2183)

Dan Rosenberg discovered that the IPv4 diagnostic routines did not
correctly validate certain requests. A local attacker could exploit this to
consume CPU resources, leading to a denial of service. (CVE-2011-2213)

Vasiliy Kulikov discovered that taskstats listeners were not correctly
handled. A local attacker could expoit this to exhaust memory and CPU
resources, leading to a denial of service. (CVE-2011-2484)

It was discovered that Bluetooth l2cap and rfcomm did not correctly
initialize structures. A local attacker could exploit this to read portions
of the kernel stack, leading to a loss of privacy. (CVE-2011-2492)

Mauro Carvalho Chehab discovered that the si4713 radio driver did not
correctly check the length of memory copies. If this hardware was
available, a local attacker could exploit this to crash the system or gain
root privileges. (CVE-2011-2700)

Herbert Xu discovered that certain fields were incorrectly handled when
Generic Receive Offload (CVE-2011-2723)

Vasiliy Kulikov discovered that the Comedi driver did not correctly clear
memory. A local attacker could exploit this to read kernel stack memory,
leading to a loss of privacy. (CVE-2011-2909)

The performance counter subsystem did not correctly handle certain
counters. A local attacker could exploit this to crash the system, leading
to a denial of service. (CVE-2011-2918)

A flaw was found in the Linux kernel's /proc//map* interface. A local,
unprivileged user could exploit this flaw to cause a denial of service.
(CVE-2011-3637)

Ben Hutchings discovered several flaws in the Linux Rose (X.25 PLP) layer.
A local user or a remote user on an X.25 network could exploit these flaws
to execute arbitrary code as root. (CVE-2011-4914)


Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
10.04 lucid linux-image-2.6.32-318-ec2 –  2.6.32-318.38

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