=========================================================================
Ubuntu Security Notice USN-3901-1
March 05, 2019

linux, linux-aws, linux-gcp, linux-kvm, linux-oem, linux-oracle, linux-raspi2 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS

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 access to
services that cache authorizations. (CVE-2019-6133)

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.

References:
  https://usn.ubuntu.com/usn/usn-3901-1
  CVE-2018-18397, CVE-2018-19854, CVE-2019-6133

Package Information:
  https://launchpad.net/ubuntu/+source/linux/4.15.0-46.49
  https://launchpad.net/ubuntu/+source/linux-aws/4.15.0-1033.35
  https://launchpad.net/ubuntu/+source/linux-gcp/4.15.0-1028.29
  https://launchpad.net/ubuntu/+source/linux-kvm/4.15.0-1030.30
  https://launchpad.net/ubuntu/+source/linux-oem/4.15.0-1034.39
  https://launchpad.net/ubuntu/+source/linux-oracle/4.15.0-1009.11
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1032.34