CATALOG READ controls to what extent a user can access data in SAP HANA dictionary tables (e.g. TABLE_COLUMNS or INDEXES). If CATALOG READ is granted, all information is visible. If CATALOG READ isn't granted, only the information for own objects is shown. At the same time the performance of these dictionary queries can be worse due to the required security checks.
Unlike on other databases a missing CATALOG READ right doesn't result in an error, it just restricts the result set of dictionary queries.