A Linux firmware security update has been released for Ubuntu 18.04 LTS and 16.04 LTS.

USN-4351-1: Linux firmware vulnerability

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Ubuntu Security Notice USN-4351-1
May 06, 2020

linux-firmware vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

The system could be made to expose sensitive information.

Software Description:
- linux-firmware: Firmware for Linux kernel drivers

Details:

Eli Biham and Lior Neumann discovered that certain Bluetooth devices
incorrectly validated key exchange parameters. An attacker could possibly
use this issue to obtain sensitive information.

Update instructions:

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

Ubuntu 18.04 LTS:
linux-firmware 1.173.18

Ubuntu 16.04 LTS:
linux-firmware 1.157.23

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
  https://usn.ubuntu.com/4351-1
CVE-2018-5383

Package Information:
  https://launchpad.net/ubuntu/+source/linux-firmware/1.173.18
  https://launchpad.net/ubuntu/+source/linux-firmware/1.157.23