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

Ubuntu Security Notice USN-1216-1

26th September, 2011

linux-ec2 vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 10.04 LTS

Summary

Multiple kernel flaws have been fixed.

Software description

  • linux-ec2 - Linux kernel for EC2

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 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

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

Ubuntu 10.04 LTS:
linux-image-2.6.32-318-ec2 2.6.32-318.38

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

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.

References

CVE-2010-4076, CVE-2010-4077, CVE-2010-4251, CVE-2010-4805, CVE-2011-1020, CVE-2011-1493, CVE-2011-1577, CVE-2011-1585, CVE-2011-1767, CVE-2011-1768, CVE-2011-2182, CVE-2011-2183, CVE-2011-2213, CVE-2011-2484, CVE-2011-2492, CVE-2011-2700, CVE-2011-2723, CVE-2011-2909, CVE-2011-2918, CVE-2011-3637, CVE-2011-4914