sudo needs updating to 1.8.28, due to security flaw (CVE-2019-14287)
https://thehackernews.com/2019/10/linux-sudo-run-as-root-flaw.html
https://www.sudo.ws/alerts/minus_1_uid.html
Summary: When sudo is configured to allow a user to run commands as an arbitrary user via the ALL keyword in a Runas specification, it is possible to run commands as root by specifying the user ID -1 or 4294967295. This can be used by a user with sufficient sudo privileges to run commands as root even if the Runas specification explicitly disallows root access as long as the ALL keyword is listed first in the Runas specification.
Log entries for commands run this way will list the target user as 4294967295 instead of root. In addition, PAM session modules will not be run for the command.
Sudo versions affected: Sudo versions prior to 1.8.28 are affected. CVE ID: This vulnerability has been assigned CVE-2019-14287 in the Common Vulnerabilities and Exposures database.