USN-1776-1: Linux kernel (EC2) vulnerabilities

22 March 2013

linux-ec2 vulnerabilities

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

  • Ubuntu 10.04 LTS

Summary

Several security issues were fixed in the kernel.

Software Description

  • linux-ec2 - Linux kernel for EC2

Details

A flaw was reported in the permission checks done by the Linux kernel for /dev/cpu/*/msr. A local root user with all capabilities dropped could exploit this flaw to execute code with full root capabilities. (CVE-2013-0268)

A flaw was discovered in the Linux kernels handling of memory ranges with PROT_NONE when transparent hugepages are in use. An unprivileged local user could exploit this flaw to cause a denial of service (crash the system). (CVE-2013-0309)

A flaw was discovered on the Linux kernel’s VFAT filesystem driver when a disk is mounted with the utf8 option (this is the default on Ubuntu). On a system where disks/images can be auto-mounted or a FAT filesystem is mounted an unprivileged user can exploit the flaw to gain root privileges. (CVE-2013-1773)

Update instructions

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

Ubuntu 10.04 LTS
linux-image-2.6.32-351-ec2 - 2.6.32-351.62

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