sssd up to 1.15.x Password Hash sysdb_search_user_by_upn_res() information disclosure

A vulnerability classified as problematic was found in sssd up to 1.15.x. Affected by this vulnerability is the function sysdb_search_user_by_upn_res() of the component Password Hash Handler. Upgrading to version 1.16.0 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.