/usr/lib/x86_64-linux-gnu/sasl2/libldapdb.so.2 is in libsasl2-modules-ldap 2.1.26.dfsg1-14build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/sasl2/libldapdb.so.2.0.25
/usr/lib/x86_64-linux-gnu/sasl2/libldapdb.so.2.0.25