2020 LDAP channel binding and LDAP signing requirement for Windows

[FredPenner]

I have an application that uses the PHP LDAP library to connect to the Windows Active Directory:

$ds = ldap_connect($ini['ad_server']) or die("Could not connect");
$admin = $ini['ad_user'];
$passwd = $ini['ad_password'];
$passwd = base64_decode($passwd);
$dn = $ini['ad_basedn'];

ldap_set_option($ds, LDAP_OPT_PROTOCOL_VERSION, 3);
ldap_set_option($ds, LDAP_OPT_REFERRALS, 0);
$rInTouch = ldap_bind($ds, $admin, $passwd);

I am wondering if anyone knows if this upcoming patch "2020 LDAP channel binding and LDAP signing" coming from Microsoft will break any PHP applications that are using this ldap library.

Thanks in advance,

 

M

[requinix]

Note that they're talking about changing default settings.

Make the recommended changes on your server and see what happens. Really. That's going to be the most effective way to gauge the impact.

[kicken]

We have an app that supports LDAP auth (but we don't use it) so I tried to setup an active directory VM and apply those settings to test this.

Assuming I did it right, then it seems that so long as you connect to the LDAP server using TLS then everything is fine.  This means either using a ldaps:// url in ldap_connect or using ldap_start_tls after connecting.  Only unencrypted connections stopped working for me when applying those configuration changes.

I'm not well-versed in LDAP or Active Directory so there's a chance I didn't do something right in the setup/configuration but I think I got it done right so I'd probably not be too worried about the change, just make sure you use an encrypted connection to the ldap server.