Delegated Authentication

CAS can act as a client (i.e. service provider or proxy) using the Pac4j library and delegate the authentication to:

  • CAS servers
  • SAML2 identity providers
  • OAuth2 providers such as Facebook, Twitter, GitHub, Google, LinkedIn, etc
  • OpenID Connect identity providers such as Google, Apple
  • ADFS

Support is enabled by including the following dependency in the WAR overlay:

implementation "org.apereo.cas:cas-server-support-pac4j-webflow:${project.'cas.version'}"
dependencyManagement {
  imports {
    mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"

dependencies {  
  implementation "org.apereo.cas:cas-server-support-pac4j-webflow"

The following settings and properties are available from the CAS configuration catalog:

The configuration settings listed below are tagged as Required in the CAS configuration metadata. This flag indicates that the presence of the setting may be needed to activate or affect the behavior of the CAS feature and generally should be reviewed, possibly owned and adjusted. If the setting is assigned a default value, you do not need to strictly put the setting in your copy of the configuration, but should review it nonetheless to make sure it matches your deployment expectations.

  • cas.authn.pac4j.core.groovy-redirection-strategy.location=
  • The location of the resource. Resources can be URLS, or files found either on the classpath or outside somewhere in the file system.


    The configuration settings listed below are tagged as Optional in the CAS configuration metadata. This flag indicates that the presence of the setting is not immediately necessary in the end-user CAS configuration, because a default value is assigned or the activation of the feature is not conditionally controlled by the setting value.

  • cas.authn.pac4j.core.lazy-init=true
  • Whether initialization of delegated identity providers should be done eagerly typically during startup.

  • The name of the authentication handler in CAS used for delegation.

  • cas.authn.pac4j.core.order=
  • Order of the authentication handler in the chain.

  • cas.authn.pac4j.core.principal-attribute-id=
  • The attribute to use as the principal identifier built during and upon a successful authentication attempt.

  • cas.authn.pac4j.core.replicate-sessions=true
  • Indicates whether profiles and other session data, collected as part of pac4j flows and requests that are kept by the container session, should be replicated across the cluster using CAS and its own ticket registry. Without this option, profile data and other related pieces of information should be manually replicated via means and libraries outside of CAS.

  • cas.authn.pac4j.core.typed-id-used=false
  • When constructing the final user profile from the delegated provider, determines if the provider id should be combined with the principal id.