Information
The default "include" directory should be specified for the /etc/sudoers file. It allows adding separate sudo privilege files for specified users or groups, keeping the main sudoers file organized and reducing the risk of error.
The sudo command allows authorized users to run programs (including shells) as other users, system users, and root. The /etc/sudoers file is used to configure authorized sudo users as well as the programs they are allowed to run. Some configuration options in the /etc/sudoers file allow configured users to run programs without re-authenticating. Use of these configuration options makes it easier for one compromised account to be used to compromise other accounts.
It is possible to include other sudoers files from within the sudoers file currently being parsed using the #include and #includedir directives. When sudo reaches this line it will suspend processing of the current file ( /etc/sudoers ) and switch to the specified file/directory. Once the end of the included file(s) is reached, the rest of /etc/sudoers will be processed. Files that are included may themselves include other files. A hard limit of 128 nested include files is enforced to prevent include file loops.
Solution
Edit the /etc/sudoers file to only include the /etc/sudoers.d directory with visudo -f <PATH TO FILE> and add or modify the following line:
#includedir /etc/sudoers.d
Impact:
If the include and includedir directives are not present in the /etc/sudoers file, this requirement is not applicable.