libldap in certain third-party OpenLDAP packages has a certificate-validation flaw when the third-party package is asserting RFC6125 support. It considers CN even when there is a non-matching subjectAltName (SAN). This is fixed in, for example, openldap-2.4.46-10.el8 in Red Hat Enterprise Linux.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-15719
Reference (s):
- https://kc.mcafee.com/corporate/index?page=content&id=SB10365
- https://access.redhat.com/errata/RHBA-2019:3674
- https://bugs.openldap.org/show_bug.cgi?id=9266
- https://bugzilla.redhat.com/show_bug.cgi?id=1740070
- SUSE:openSUSE-SU-2020:1416