=========================================================================Ubuntu Security Notice USN-5149-1
November 16, 2021

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

- Ubuntu 21.10
- Ubuntu 21.04
- Ubuntu 20.04 LTS

Summary:

AccountsService could be made to crash or run programs as an administrator
if it received a specially crafted command.

Software Description:
- accountsservice: query and manipulate user account information

Details:

Kevin Backhouse discovered that AccountsService incorrectly handled memory
when performing certain language setting operations. A local attacker could
use this issue to escalate privileges.

Update instructions:

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

Ubuntu 21.10:
  accountsservice                 0.6.55-0ubuntu14.1
  libaccountsservice0             0.6.55-0ubuntu14.1

Ubuntu 21.04:
  accountsservice                 0.6.55-0ubuntu13.3
  libaccountsservice0             0.6.55-0ubuntu13.3

Ubuntu 20.04 LTS:
  accountsservice                 0.6.55-0ubuntu12~20.04.5
  libaccountsservice0             0.6.55-0ubuntu12~20.04.5

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

References:
  https://ubuntu.com/security/notices/USN-5149-1
  CVE-2021-3939

Package Information:
  https://launchpad.net/ubuntu/+source/accountsservice/0.6.55-0ubuntu14.1
  https://launchpad.net/ubuntu/+source/accountsservice/0.6.55-0ubuntu13.3
  https://launchpad.net/ubuntu/+source/accountsservice/0.6.55-0ubuntu12~20.04.5