GEN000280 - Direct logins must not be permitted to shared, default, application, or utility accounts - 'results of last should be reviewed'
Shared accounts (accounts where two or more people log in with the same user identification) do not provide identification and authentication. There is no way to provide for non-repudiation or individual accountability.
Use the switch user (su) command from a named account login to access shared accounts. Maintain audit trails to identify the actual user of that account name. Document requirements and procedures for users/administrators to log into their own accounts first and then switch user (su) to the account that must be shared. Direct login to shared or application accounts can be prevented by setting the rlogin = false in the accounts stanza of the /etc/security/user file. Additional hardening of the shared/application accounts can be done with the sugroups = in the accounts stanza of the /etc/security/user file. #chuser rlogin=false < user id >