N/A - USN-2852-1

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

- Ubuntu 15.10

Summary:

The system could be made to provide access outside of namespace sandbox.

Software Description: - linux-raspi2: Linux kernel for Raspberry Pi 2

Details:

Jann Horn discovered a ptrace issue with user namespaces in the Linux kernel. The namespace owner could potentially exploit this flaw by ptracing a root owned process entering the user namespace to elevate its privileges and potentially gain access outside of the namespace. (http://bugs.launchpad.net/bugs/1527374)

Update instructions:

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

Ubuntu 15.10:
linux-image-4.2.0-1017-raspi2 4.2.0-1017.24

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. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well.

References:
http://www.ubuntu.com/usn/usn-2852-1
http://bugs.launchpad.net/bugs/1527374

Package Information:
https://launchpad.net/ubuntu/+source/linux-raspi2/4.2.0-1017.24