The OAuth Single Sign On Free WordPress plugin before 6.24.2, OAuth Single Sign On Standard WordPress plugin before 28.4.9, OAuth Single Sign On Premium WordPress plugin before 38.4.9 and OAuth Single Sign On Enterprise WordPress plugin before 48.4.9 do not have CSRF checks when deleting Identity Providers (IdP), which could allow attackers to make logged in admins delete arbitrary IdP via a CSRF attack

The OAuth Single Sign On WordPress plugin before 6.24.2 does not have CSRF checks when discarding Identify providers (IdP), which could allow attackers to make logged in admins delete all IdP via a CSRF attack

The OAuth Single Sign On WordPress plugin before 6.22.6 doesn't validate that OAuth access token requests are legitimate, which allows attackers to log onto the site with the only knowledge of a user's email address.

In the OAuth2 Client extension before 0.4 for MediaWiki, a CSRF vulnerability exists due to the OAuth2 state parameter not being checked in the callback function.