=========================================================================Ubuntu Security Notice USN-5279-1
February 09, 2022

util-linux vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 21.10
- Ubuntu 20.04 LTS

Summary:

util-linux could be made to unmount FUSE filesystems belonging to other
users.

Software Description:
- util-linux: miscellaneous system utilities

Details:

It was discovered that util-linux incorrectly handled unmounting FUSE
filesystems. A local attacker could possibly use this issue to unmount
FUSE filesystems belonging to other users.

Update instructions:

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

Ubuntu 21.10:
  mount                           2.36.1-8ubuntu2.2
  util-linux                      2.36.1-8ubuntu2.2

Ubuntu 20.04 LTS:
  mount                           2.34-0.1ubuntu9.3
  util-linux                      2.34-0.1ubuntu9.3

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

References:
  https://ubuntu.com/security/notices/USN-5279-1
  CVE-2021-3995, CVE-2021-3996

Package Information:
  https://launchpad.net/ubuntu/+source/util-linux/2.36.1-8ubuntu2.2
  https://launchpad.net/ubuntu/+source/util-linux/2.34-0.1ubuntu9.3