Information
The SYSCAT.ROLES view contains all roles available in the database. It is recommended that the PUBLIC role be restricted from accessing this view.
Rationale:
PUBLIC should not have access to see all the roles because this could be used as a point of exploit.
Solution
Perform the following to revoke access from PUBLIC.
Connect to the Db2 database.
db2 => connect to <dbname>
Run the following command:
db2 => REVOKE SELECT ON SYSCAT.ROLES FROM PUBLIC