diff --git a/federation/kerberos/src/main/java/org/keycloak/federation/kerberos/KerberosFederationProvider.java b/federation/kerberos/src/main/java/org/keycloak/federation/kerberos/KerberosFederationProvider.java
index 09a4da7..65831f2 100755
--- a/federation/kerberos/src/main/java/org/keycloak/federation/kerberos/KerberosFederationProvider.java
+++ b/federation/kerberos/src/main/java/org/keycloak/federation/kerberos/KerberosFederationProvider.java
@@ -116,7 +116,7 @@ public class KerberosFederationProvider implements UserFederationProvider {
// KerberosUsernamePasswordAuthenticator.isUserAvailable is an overhead, so avoid it for now
String kerberosPrincipal = local.getUsername() + "@" + kerberosConfig.getKerberosRealm();
- return kerberosPrincipal.equals(local.getFirstAttribute(KERBEROS_PRINCIPAL));
+ return kerberosPrincipal.equalsIgnoreCase(local.getFirstAttribute(KERBEROS_PRINCIPAL));
}
@Override