Ubuntu 20.04 LTS Security Advisory USN-4591-1: Critical Kernel Issues

ubuntu

October 19, 2020

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-raspi: Linux kernel for Raspberry Pi (V8) systems

- linux-hwe-5.4: Linux hardware enablement (HWE) kernel

- linux-oem: Linux kernel for OEM systems

- linux-raspi-5.4: Linux kernel for Raspberry Pi (V8) systems

- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors- linux-hwe: Linux hardware enablement (HWE) kernel

Details:

Andy Nguyen discovered that the Bluetooth L2CAP implementation in the Linux

kernel contained a type-confusion error. A physically proximate remote

attacker could use this to cause a denial of service (system crash) or

possibly execute arbitrary code. (CVE-2020-12351)

Andy Nguyen discovered that the Bluetooth A2MP implementation in the Linux

kernel did not properly initialize memory in some situations. A physically

proximate remote attacker could use this to expose sensitive information

(kernel memory). (CVE-2020-12352)

Topics Covered

security advisory denial of service software update Ubuntu kernel information exposure Bluetooth

Update Instructions

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

Ubuntu 20.04 LTS:
  linux-image-5.4.0-1022-raspi    5.4.0-1022.25
  linux-image-5.4.0-52-generic    5.4.0-52.57
  linux-image-5.4.0-52-generic-lpae  5.4.0-52.57
  linux-image-5.4.0-52-lowlatency  5.4.0-52.57
  linux-image-generic             5.4.0.52.55
  linux-image-generic-hwe-18.04   5.4.0.52.55
  linux-image-generic-hwe-18.04-edge  5.4.0.52.55
  linux-image-generic-hwe-20.04   5.4.0.52.55
  linux-image-generic-lpae        5.4.0.52.55
  linux-image-generic-lpae-hwe-18.04  5.4.0.52.55
  linux-image-generic-lpae-hwe-18.04-edge  5.4.0.52.55
  linux-image-generic-lpae-hwe-20.04  5.4.0.52.55
  linux-image-lowlatency          5.4.0.52.55
  linux-image-lowlatency-hwe-18.04  5.4.0.52.55
  linux-image-lowlatency-hwe-18.04-edge  5.4.0.52.55
  linux-image-lowlatency-hwe-20.04  5.4.0.52.55
  linux-image-oem                 5.4.0.52.55
  linux-image-oem-osp1            5.4.0.52.55
  linux-image-raspi               5.4.0.1022.57
  linux-image-raspi-hwe-18.04     5.4.0.1022.57
  linux-image-raspi-hwe-18.04-edge  5.4.0.1022.57
  linux-image-raspi2              5.4.0.1022.57
  linux-image-raspi2-hwe-18.04    5.4.0.1022.57
  linux-image-raspi2-hwe-18.04-edge  5.4.0.1022.57
  linux-image-virtual             5.4.0.52.55
  linux-image-virtual-hwe-18.04   5.4.0.52.55
  linux-image-virtual-hwe-18.04-edge  5.4.0.52.55
  linux-image-virtual-hwe-20.04   5.4.0.52.55

Ubuntu 18.04 LTS:
  linux-image-4.15.0-1090-snapdragon  4.15.0-1090.99
  linux-image-4.15.0-1100-oem     4.15.0-1100.110
  linux-image-4.15.0-122-generic  4.15.0-122.124
  linux-image-4.15.0-122-generic-lpae  4.15.0-122.124
  linux-image-4.15.0-122-lowlatency  4.15.0-122.124
  linux-image-5.4.0-1022-raspi    5.4.0-1022.25~18.04.1
  linux-image-5.4.0-52-generic    5.4.0-52.57~18.04.1
  linux-image-5.4.0-52-generic-lpae  5.4.0-52.57~18.04.1
  linux-image-5.4.0-52-lowlatency  5.4.0-52.57~18.04.1
  linux-image-generic             4.15.0.122.109
  linux-image-generic-hwe-18.04   5.4.0.52.57~18.04.46
  linux-image-generic-lpae        4.15.0.122.109
  linux-image-generic-lpae-hwe-18.04  5.4.0.52.57~18.04.46
  linux-image-lowlatency          4.15.0.122.109
  linux-image-lowlatency-hwe-18.04  5.4.0.52.57~18.04.46
  linux-image-oem                 4.15.0.1100.104
  linux-image-powerpc-e500mc      4.15.0.122.109
  linux-image-powerpc-smp         4.15.0.122.109
  linux-image-powerpc64-emb       4.15.0.122.109
  linux-image-powerpc64-smp       4.15.0.122.109
  linux-image-raspi-hwe-18.04     5.4.0.1022.26
  linux-image-snapdragon          4.15.0.1090.93
  linux-image-snapdragon-hwe-18.04  5.4.0.52.57~18.04.46
  linux-image-virtual             4.15.0.122.109
  linux-image-virtual-hwe-18.04   5.4.0.52.57~18.04.46

Ubuntu 16.04 LTS:
  linux-image-4.15.0-122-generic  4.15.0-122.124~16.04.1
  linux-image-4.15.0-122-generic-lpae  4.15.0-122.124~16.04.1
  linux-image-4.15.0-122-lowlatency  4.15.0-122.124~16.04.1
  linux-image-generic-hwe-16.04   4.15.0.122.122
  linux-image-generic-hwe-16.04-edge  4.15.0.122.122
  linux-image-generic-lpae-hwe-16.04  4.15.0.122.122
  linux-image-generic-lpae-hwe-16.04-edge  4.15.0.122.122
  linux-image-lowlatency-hwe-16.04  4.15.0.122.122
  linux-image-lowlatency-hwe-16.04-edge  4.15.0.122.122
  linux-image-oem                 4.15.0.122.122
  linux-image-virtual-hwe-16.04   4.15.0.122.122
  linux-image-virtual-hwe-16.04-edge  4.15.0.122.122

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.