/usr/lib/ldap/collect.so is in slapd 2.4.40+dfsg-1+deb8u4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ldap/collect-2.4.so.2.10.3
/usr/lib/ldap/collect-2.4.so.2.10.3