Can confirm this with openldap 2.4.24.

Using ldap search filters like this: (cn=blabla' or '1'='1) is at least causing my postgres to eat all CPU cycles it can get (LDAP data is based on complex view). I do not have write access enabled for that particular openLDAP installation, but I also assume that SQL Injection is possible. Beside being an obviuos malfunction, this should be considered a security issue.