A cryptsetup security update has been released for Ubuntu Linux 20.04 LTS and 21.10.

==========================================================================
Ubuntu Security Notice USN-5286-1
February 15, 2022

cryptsetup vulnerability
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 21.10
- Ubuntu 20.04 LTS

Summary:

cryptsetup could be made to expose sensitive information.

Software Description:
- cryptsetup: disk encryption support

Details:

Milan Broz discovered that cryptsetup incorrectly handled LUKS2
reencryption recovery. An attacker with physical access to modify the
encrypted device header may trigger the device to be unencrypted the next
time it is mounted by the user.

On Ubuntu 20.04 LTS, this issue was fixed by disabling the online
reencryption feature.

Update instructions:

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

Ubuntu 21.10:
cryptsetup 2:2.3.7-0ubuntu0.21.10.1

Ubuntu 20.04 LTS:
cryptsetup 2:2.2.2-3ubuntu2.4

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-5286-1
CVE-2021-4122

Package Information:
  https://launchpad.net/ubuntu/+source/cryptsetup/2:2.3.7-0ubuntu0.21.10.1
  https://launchpad.net/ubuntu/+source/cryptsetup/2:2.2.2-3ubuntu2.4