USN-3594-1: Linux kernel vulnerability

9 March 2018

linux vulnerability

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

  • Ubuntu 14.04 LTS

Summary

The system could be made to expose sensitive information.

Software Description

  • linux - Linux kernel

Details

USN-3542-1 mitigated CVE-2017-5715 (Spectre Variant 2) for the amd64 architecture in Ubuntu 14.04 LTS. This update provides the compiler-based retpoline kernel mitigation for the amd64 and i386 architectures. Original advisory details:

Jann Horn discovered that microprocessors utilizing speculative execution and branch prediction may allow unauthorized memory reads via sidechannel attacks. This flaw is known as Spectre. A local attacker could use this to expose sensitive information, including kernel memory. (CVE-2017-5715)

Update instructions

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

Ubuntu 14.04 LTS
linux-image-3.13.0-143-generic - 3.13.0-143.192
linux-image-3.13.0-143-generic-lpae - 3.13.0-143.192
linux-image-3.13.0-143-lowlatency - 3.13.0-143.192
linux-image-generic - 3.13.0.143.153
linux-image-generic-lpae - 3.13.0.143.153
linux-image-lowlatency - 3.13.0.143.153

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