Ubuntu 18.04 LTS: USN-3901-1 Moderate: Linux Kernel Issues

ubuntu

March 5, 2019

Several security issues were fixed in the Linux kernel.

Summary

Several security issues were fixed in the Linux kernel.

Software Description:

- 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

Details:

Jann Horn discovered that the userfaultd implementation in the Linux kernel

did not properly restrict access to certain ioctls. A local attacker could

use this possibly to modify files. (CVE-2018-18397)

It was discovered that the crypto subsystem of the Linux kernel leaked

uninitialized memory to user space in some situations. A local attacker

could use this to expose sensitive information (kernel memory).

(CVE-2018-19854)

Jann Horn discovered a race condition in the fork() system call in

the Linux kernel. A local attacker could use this to gain acces...

Read the Full Advisory

Topics Covered

security advisory security issue local attack information exposure ubuntu linux kernel services access

Update Instructions

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

Ubuntu 18.04 LTS:
  linux-image-4.15.0-1009-oracle  4.15.0-1009.11
  linux-image-4.15.0-1028-gcp     4.15.0-1028.29
  linux-image-4.15.0-1030-kvm     4.15.0-1030.30
  linux-image-4.15.0-1032-raspi2  4.15.0-1032.34
  linux-image-4.15.0-1033-aws     4.15.0-1033.35
  linux-image-4.15.0-1034-oem     4.15.0-1034.39
  linux-image-4.15.0-46-generic   4.15.0-46.49
  linux-image-4.15.0-46-generic-lpae  4.15.0-46.49
  linux-image-4.15.0-46-lowlatency  4.15.0-46.49
  linux-image-4.15.0-46-snapdragon  4.15.0-46.49
  linux-image-aws                 4.15.0.1033.32
  linux-image-gcp                 4.15.0.1028.30
  linux-image-generic             4.15.0.46.48
  linux-image-generic-lpae        4.15.0.46.48
  linux-image-gke                 4.15.0.1028.30
  linux-image-kvm                 4.15.0.1030.30
  linux-image-lowlatency          4.15.0.46.48
  linux-image-oem                 4.15.0.1034.39
  linux-image-oracle              4.15.0.1009.12
  linux-image-raspi2              4.15.0.1032.30
  linux-image-snapdragon          4.15.0.46.48

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.