extremeidea

Looking for SSO tool for your WordPress and vBulletin sites?
Try vBSSO for FREE.
vBSSO-lite – is a plugin that provides universal Secure Single Sign-On between vBulletin and WordPress – allows users to sign in to WordPress using vBulletin credentials.
The plugin consists of two synchronization vBulletin (acts as a Master) and WordPress (acts as a Slave) lightweight extensions where vBulletin holds the master users database and all the user-related operations are managed there.
The list of features:
<ol>
<li>Login.</li>
<li>Logout.</li>
<li>Registration.</li>
<li>The vBSSO footer link is available only on wp-admin.</li>
</ol>
Read more about <a href="https://www.vbsso.com/" rel="nofollow ugc">vBSSO</a>. 
The plugin is developed and supported by <a href="https://www.extreme-idea.com/" rel="nofollow ugc">Extreme Idea LLC</a>. Our entire team is ready to help you. Ask your questions in the support forum, or <a href="https://www.extreme-idea.com/contact-us/" rel="nofollow ugc">contact us directly</a>.
<h3>Uninstallation</h3>
To Uninstall the WordPress SSO extension: 
1. Log in as WordPress administrator to WordPress Admin Panel: 
2. Navigate to Plugins > press Installed Plugins button > navigate to the vBSSO extension. 
3. Press Deactivate button. 
4. Press Delete button. The plugin should be successfully deleted.
To Uninstall the extension via the vBulletin dashboard: 
1. Log in to your forum’s /admincp/ control panel as administrator. 
2. Navigate to the Plugins & Products section. 
3. Expand section and click on the Manage Products link. 
4. Find vBSSO extension and select Uninstall.
<h3>Configuration</h3>
How to connect the platforms:
CONFIGURATION, CASE 1
<ol>
<li>Log in to WordPress as administrator.</li>
<li>Navigate to Settings -> vBSSO.</li>
<li>Modify your default Platform Shared Key by setting it to more secure unreadable phrase to encrypt exchanged data.</li>
<li>Save Changes.</li>
</ol>
CONFIGURATION, CASE 2
<ol>
<li>Log in to your vBulletin control panel as administrator.</li>
<li>Navigate to vBSSO section.</li>
<li>Expand section and click on the Platforms link.</li>
<li>Copy Platform Url link and Shared Key field from WordPress installation to vBulletin.</li>
<li>Click on Connect button to connect your new platform.</li>
<li>Back to WordPress vBSSO Settings page and verify that API Connections fields are filled out.</li>
</ol>
<h3>Error Log</h3>
<ol>
<li>Log in to your forum’s /admincp/ control panel as administrator.</li>
<li>Navigate to vBSSO section.</li>
<li>Expand section and click on the Logging & Notifications link.</li>
<li>Set ‘Logging Level’ to ‘All’ and specify your email address to receive the debug information.</li>
</ol>
If you don’t need to receive debug messages, clean up your email address field and switch ‘Logging Level’ to ‘Warn’.

vBSSO-lite

Looking for SSO tool for your WordPress and vBulletin sites?

onelogin

This SAML plugin eliminates passwords and allows you to authenticate WordPress users (typically editors) against your existing Active Directory or LDAP server as well increase security using YubiKeys or VeriSign VIP Access via OneLogin. OneLogin is pre-integrated with thousands of apps and handles all of your SSO needs in the cloud and behind the firewall.
<ul>
<li>Eliminate passwords in WordPress</li>
<li>Allow users to sign into WordPress with their Active Directory or LDAP credentials</li>
<li>Give users one-click access from your intranet</li>
<li>Increase security using browser PKI certificates or two-factor authentication from Yubico or VeriSign</li>
<li>Easily prevent access from former employees and contractors</li>
</ul>
If you used this plugin before 2.2.0 with just-in-time provision active, Read: https://wpvulndb.com/vulnerabilities/8508 
To mitigate that bug, place the script at the root of wordpress and execute it (later remove it) https://gist.github.com/pitbulk/a8223c90a3534e9a7d5e0a93009a094f

OneLogin SAML SSO

This plugin provides single sign-on via SAML and gives users one-click access to their WordPress accounts from identity providers like OneLogin.

vBSSO-lite vs OneLogin SAML SSO