Cool Solution - LDAP search user / simple authentication account
From Univention Wiki
For security reasons we recommend to create a simple authentication user, which can only read LDAP entries.
First things first you go to the UMC and open the Users module and a new user. Klick on Advanced in the new Window.
Fill out all neccessary text fields (lastname, username and a safety password) and go to the "Option" tab. Untag all checkboxes except "simple authentication".