USN-1268-1: Linux kernel vulnerabilities

21 November 2011

Several security issues were fixed in the kernel.

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Releases

Packages

Details

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)

Vasily Averin discovered that the NFS Lock Manager (NLM) incorrectly
handled unlock requests. A local attacker could exploit this to cause a
denial of service. (CVE-2011-2491)

Robert Swiecki discovered that mapping extensions were incorrectly handled.
A local attacker could exploit this to crash the system, leading to a
denial of service. (CVE-2011-2496)

Ben Pfaff discovered that Classless Queuing Disciplines (qdiscs) were being
incorrectly handled. A local attacker could exploit this to crash the
system, leading to a denial of service. (CVE-2011-2525)

Yasuaki Ishimatsu discovered a flaw in the kernel's clock implementation. A
local unprivileged attacker could exploit this causing a denial of service.
(CVE-2011-3209)

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Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

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Update instructions

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

Ubuntu 8.04

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.