It was found that 389-ds-base since 1.3.6.1 up to and including 1.4.0.3 did not always handle internal hash comparison operations correctly during the authentication process. A remote, unauthenticated attacker could potentially use this flaw to bypass the authentication process under very rare and specific circumstances.
https://bugzilla.redhat.com/show_bug.cgi?id=1525628
https://access.redhat.com/errata/RHSA-2018:0515
https://access.redhat.com/errata/RHSA-2018:0414
http://www.securityfocus.com/bid/102811
http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00033.html