Application sudo, that serves for to increase rights for specific users in Linux distributions contains a critical safety issue CVE-2021–3156. It allows to obtain unauthorized rights to any local user that is located in the system. It can be even users that are not located in the configuration file sudoers.
Vulnerability exists from the versions 1.9.0 till 1.9.5p1 and older versions 1.8.2 to 1.8.31p2. It touches to the most of the current distrubutions.
This safety issue is patched in the version sudo 1.9.5p2, to which we recommend to upgrade.