For reports we apply the security in Cognos connection. Go to cc from the actions->setpropertiesicon->permissions->click the check box overide the permission and then set required properties to protect to your reports.
Let me know if you have any another solution.
Thanks siva
Above answer was rated as good by the following members: sandeep8000861
Security can be applied on the reports that will be generated at the Framework Manager level as well by giving rights to user groups to the package or individual query subjects while publishing the package.
For reports we apply the security in Cognos connection. Go to cc from the actions->setpropertiesicon->permissions->click the check box overide the permission and then set required properties to protect to your reports.