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.