V-271188

Discussion

In certain situations, to provide required functionality, a DBMS must execute internal logic (stored procedures, functions, triggers, etc.) and/or external code modules with elevated privileges. However, if the privileges required for execution are at a higher level than the privileges assigned to organizational users invoking the functionality applications/programs, those users are indirectly provided with greater privileges than assigned by organizations. Privilege elevation must be used only where necessary and protected from misuse. This calls for inspection of application source code, which will require collaboration with the application developers. It is recognized that in many cases, the database administrator (DBA) is organizationally separate from the application developers, and may have limited, if any, access to source code. Nevertheless, protections of this type are so important to the secure operation of databases that they must not be ignored. At a minimum, the DBA must attempt to obtain assurances from the development organization that this issue has been addressed and must document what has been discovered.

Check Content

Review the system documentation to obtain a listing of stored procedures and functions that use impersonation. Execute the following query:

SELECT S.name AS schema_name, O.name AS module_name,
USER_NAME(
CASE M.execute_as_principal_id
WHEN -2 THEN COALESCE(O.principal_id, S.principal_id)
ELSE M.execute_as_principal_id
END
) AS execute_as
FROM sys.sql_modules M
JOIN sys.objects O ON M.object_id = O.object_id
JOIN sys.schemas S ON O.schema_id = S.schema_id
WHERE execute_as_principal_id IS NOT NULL
and       O.name not in 
(             
'fn_sysdac_get_username',
                             'fn_sysutility_ucp_get_instance_is_mi',
                             'sp_send_dbmail',
                             'sp_SendMailMessage',
                             'sp_syscollector_create_collection_set',
                             'sp_syscollector_delete_collection_set',
                             'sp_syscollector_disable_collector',
                             'sp_syscollector_enable_collector',
                             'sp_syscollector_get_collection_set_execution_status',
                             'sp_syscollector_run_collection_set',
                             'sp_syscollector_start_collection_set',
                             'sp_syscollector_update_collection_set',
                             'sp_syscollector_upload_collection_set',
                             'sp_syscollector_verify_collector_state',
                             'sp_syspolicy_add_policy',
                             'sp_syspolicy_add_policy_category_subscription',
                             'sp_syspolicy_delete_policy',
                             'sp_syspolicy_delete_policy_category_subscription',
                             'sp_syspolicy_update_policy',
                             'sp_sysutility_mi_add_ucp_registration',
                             'sp_sysutility_mi_disable_collection',
                             'sp_sysutility_mi_enroll',
                             'sp_sysutility_mi_initialize_collection',
                             'sp_sysutility_mi_remove',
                             'sp_sysutility_mi_remove_ucp_registration',
                             'sp_sysutility_mi_upload',
                             'sp_sysutility_mi_validate_enrollment_preconditions',
                             'sp_sysutility_ucp_add_mi',
                             'sp_sysutility_ucp_add_policy',
                             'sp_sysutility_ucp_calculate_aggregated_dac_health',
                             'sp_sysutility_ucp_calculate_aggregated_mi_health',
                             'sp_sysutility_ucp_calculate_computer_health',
                             'sp_sysutility_ucp_calculate_dac_file_space_health',
                             'sp_sysutility_ucp_calculate_dac_health',
                             'sp_sysutility_ucp_calculate_filegroups_with_policy_violations',
                             'sp_sysutility_ucp_calculate_health',
                             'sp_sysutility_ucp_calculate_mi_file_space_health',
                             'sp_sysutility_ucp_calculate_mi_health',
                             'sp_sysutility_ucp_configure_policies',
                             'sp_sysutility_ucp_create',
                             'sp_sysutility_ucp_delete_policy',
                             'sp_sysutility_ucp_delete_policy_history',
                             'sp_sysutility_ucp_get_policy_violations',
                             'sp_sysutility_ucp_initialize',
                             'sp_sysutility_ucp_initialize_mdw',
                             'sp_sysutility_ucp_remove_mi',
                             'sp_sysutility_ucp_update_policy',
                             'sp_sysutility_ucp_update_utility_configuration',
                             'sp_sysutility_ucp_validate_prerequisites',
                             'sp_validate_user',
                             'syscollector_collection_set_is_running_update_trigger',
                             'sysmail_help_status_sp'
)

ORDER BY schema_name, module_name

If any procedures or functions are returned that are not documented, this is a finding.