Vulnerability Discussion
The s-nail package provides the mail command required to allow sending email notifications of unauthorized configuration changes to designated personnel.
Check
Verify that OL 9 has the s-nail package installed on the system with the following command:
$ dnf list --installed s-nail
Installed Packages
s-nail.x86_64 14.9.22-6.el9 @ol9_appstream
If the s-nail package is not installed, this is a finding.
Fix
Install the s-nail package with the following command:
$ sudo dnf install -y s-nail