Due to a programming error in SAP HANA DB Revsion 25 and previous, the function "CURRENT_USER" of a SQLScript procedure in definer mode returned the calling user
Update to SAP HANA Revision 26 or later
If you run a Revision of SAP HANA SP03 you have the possibility to switch to the behaviour of SAP HANA db Revision 25 or previous.
The switch can be done by setting in Revision 26 or later in HDBIndexserver.ini:
use_old_current_user_semantic = true
The HDBIndexserver needs to be restarted to activate the setting