Ubuntu 18.04 LTS USN-4711-1 Moderate: Kernel Memory Exhaustion Threat

ubuntu

January 28, 2021

Several security issues were fixed in the Linux kernel.

Summary

Several security issues were fixed in the Linux kernel.

Software Description:

- linux-aws: Linux kernel for Amazon Web Services (AWS) systems

- linux-kvm: Linux kernel for cloud environments

- linux-oracle: Linux kernel for Oracle Cloud systems

- linux-raspi2: Linux kernel for Raspberry Pi (V8) systems

- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors

Details:

It was discovered that the LIO SCSI target implementation in the Linux

kernel performed insufficient identifier checking in certain XCOPY

requests. An attacker with access to at least one LUN in a multiple

backstore environment could use this to expose sensitive information or

modify data. (CVE-2020-28374)

Kiyin (尹亮) discovered that the perf subsystem in the Linux kernel did

not properly deallocate memory in some situations. A privileged attacker

could use this to cause a denial of service (kernel memory exhaustion).

(CVE-2020-25704)

Topics Covered

security advisory moderate denial of service Ubuntu kernel update instructions information exposure ubuntu dos kernel issues

Update Instructions

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

Ubuntu 18.04 LTS:
  linux-image-4.15.0-1064-oracle  4.15.0-1064.71
  linux-image-4.15.0-1078-raspi2  4.15.0-1078.83
  linux-image-4.15.0-1084-kvm     4.15.0-1084.86
  linux-image-4.15.0-1093-aws     4.15.0-1093.99
  linux-image-4.15.0-1095-snapdragon  4.15.0-1095.104
  linux-image-aws-lts-18.04       4.15.0.1093.96
  linux-image-kvm                 4.15.0.1084.80
  linux-image-oracle-lts-18.04    4.15.0.1064.74
  linux-image-raspi2              4.15.0.1078.75
  linux-image-snapdragon          4.15.0.1095.98

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.