USN-2852-1: Linux kernel (Raspberry Pi 2) vulnerability

19 December 2015

linux-raspi2 vulnerability

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, CVE-2015-8709)

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

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. 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