Ubuntu Security Notice USN-2642-1
15th June, 2015
linux-lts-trusty vulnerability
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 12.04 LTS
Summary
The system could be made to run programs as an administrator.
Software description
- linux-lts-trusty
– Linux hardware enablement kernel from Trusty
Details
Philip Pettersson discovered a privilege escalation when using overlayfs
mounts inside of user namespaces. A local user could exploit this flaw to
gain administrative privileges on the system.
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 12.04 LTS:
-
linux-image-3.13.0-55-generic-lpae
3.13.0-55.92~precise1
-
linux-image-3.13.0-55-generic
3.13.0-55.92~precise1
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.