Microsoft will introduce a change in the behavior of LDAP channel binding and LDAP signing enabled by default.
ADV190023 | Microsoft Guidance for Enabling LDAP Channel Binding and LDAP Signing
When the LDAP servers are used for user authentication, can it affect on the PAM behavior?
Release : 3.x
Component : PRIVILEGED ACCESS MANAGEMENT
If 'SSL usage' is disabled at LDAP Configuration tab for your LDAP definition, it should be affected; the connection made via LDAP to the LDAP server would not be established.
[How to Set Up LDAP Servers for User Authentication]
Please use LDAPS instead.
[PAM and LDAPS connection and Certificate]