The client secret, also called CWAP_AuthSecret, is automatically added to the application object (app registration) when the Microsoft Entra application proxy app is created.
The client secret is valid for one year. A new one-year client secret is automatically created before the current valid client secret expires. Three CWAP_AuthSecret client secrets are kept in the application object at all times.
Important
Deleting CWAP_AuthSecret breaks pre-authentication for Azure AD Application Proxy. Don't delete CWAP_AuthSecret.