USN-4007-1: Linux kernel vulnerability

04 June 2019

linux, linux-aws, linux-gcp, linux-kvm, linux-oem, linux-oracle, linux-raspi2, linux-snapdragon vulnerability

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-oem - Linux kernel for OEM processors
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

Federico Manuel Bento discovered that the Linux kernel did not properly
apply Address Space Layout Randomization (ASLR) in some situations for
setuid a.out binaries. A local attacker could use this to improve the
chances of exploiting an existing vulnerability in a setuid a.out binary.

As a hardening measure, this update disables a.out support.

Update instructions

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

Ubuntu 18.04

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