USN-1900-1: Linux kernel (EC2) vulnerabilities

04 July 2013

Several security issues were fixed in the kernel.

Releases

Packages

  • linux-ec2 - Linux kernel for EC2

Details

Dmitry Monakhov reported a race condition flaw the Linux ext4 filesystem
that can expose stale data. An unprivileged user could exploit this flaw to
cause an information leak. (CVE-2012-4508)

Dave Jones discovered that the Linux kernel's socket subsystem does not
correctly ensure the keepalive action is associated with a stream socket. A
local user could exploit this flaw to cause a denial of service (system
crash) by creating a raw socket. (CVE-2012-6657)

An information leak was discovered in the Linux kernel's tkill and tgkill
system calls when used from compat processes. A local user could exploit
this flaw to examine potentially sensitive kernel memory. (CVE-2013-2141)

Kees Cook discovered a format string vulnerability in the Broadcom B43
wireless driver for the Linux kernel. A local user could exploit this flaw
to gain administrative privileges. (CVE-2013-2852)

Update instructions

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

Ubuntu 10.04

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.