diff --git a/src/Controller/ForceLoginController.php b/src/Controller/ForceLoginController.php
index b8059f8..21793ff 100644
--- a/src/Controller/ForceLoginController.php
+++ b/src/Controller/ForceLoginController.php
@@ -5,7 +5,7 @@ namespace Drupal\cas\Controller;
 use Drupal\cas\Service\CasHelper;
 use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\HttpFoundation\RedirectResponse;
+use Drupal\Core\Routing\TrustedRedirectResponse;
 use Symfony\Component\HttpFoundation\RequestStack;
 
 class ForceLoginController implements ContainerInjectionInterface {
@@ -54,6 +54,6 @@ class ForceLoginController implements ContainerInjectionInterface {
     $cas_login_url = $this->casHelper->getServerLoginUrl($query_params);
     $this->casHelper->log("Cas forced login route, redirecting to: $cas_login_url");
 
-    return RedirectResponse::create($cas_login_url, 302);
+    return TrustedRedirectResponse::create($cas_login_url, 302);
   }
 }
diff --git a/src/Controller/LogoutController.php b/src/Controller/LogoutController.php
index 3668fb6..f585fd8 100644
--- a/src/Controller/LogoutController.php
+++ b/src/Controller/LogoutController.php
@@ -5,7 +5,7 @@ namespace Drupal\cas\Controller;
 use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Drupal\cas\Service\CasHelper;
-use Symfony\Component\HttpFoundation\RedirectResponse;
+use Drupal\Core\Routing\TrustedRedirectResponse;
 use Symfony\Component\HttpFoundation\RequestStack;
 
 class LogoutController implements ContainerInjectionInterface {
@@ -55,7 +55,7 @@ class LogoutController implements ContainerInjectionInterface {
     $this->casHelper->log("Drupal session terminated; redirecting to CAS logout at: $logout_url");
 
     // Redirect the user to the CAS logout screen.
-    return new RedirectResponse($logout_url, 302);
+    return new TrustedRedirectResponse($logout_url, 302);
   }
 
   /**
diff --git a/src/Service/CasValidator.php b/src/Service/CasValidator.php
index 3fb4a57..ca2562f 100644
--- a/src/Service/CasValidator.php
+++ b/src/Service/CasValidator.php
@@ -3,7 +3,7 @@
 namespace Drupal\cas\Service;
 
 use Drupal\cas\Exception\CasValidateException;
-use Drupal\Core\Http\Client;
+use GuzzleHttp\Client;
 use GuzzleHttp\Exception\ClientException;
 use Drupal\cas\CasPropertyBag;
 
diff --git a/src/Subscriber/CasSubscriber.php b/src/Subscriber/CasSubscriber.php
index 924be9d..bc7a1e8 100644
--- a/src/Subscriber/CasSubscriber.php
+++ b/src/Subscriber/CasSubscriber.php
@@ -8,7 +8,7 @@ namespace Drupal\cas\Subscriber;
 
 use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Session\AccountInterface;
-use Symfony\Component\HttpFoundation\RedirectResponse;
+use Drupal\Core\Routing\TrustedRedirectResponse;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\HttpKernel\HttpKernelInterface;
@@ -168,7 +168,7 @@ class CasSubscriber implements EventSubscriberInterface {
         'cas_temp_disable' => TRUE,
       ));
       $this->casHelper->log("Protected Url detected, redirecting to: $cas_login_url");
-      $event->setResponse(RedirectResponse::create($cas_login_url));
+      $event->setResponse(TrustedRedirectResponse::create($cas_login_url));
       return TRUE;
     }
     return FALSE;
@@ -220,7 +220,7 @@ class CasSubscriber implements EventSubscriberInterface {
       'cas_temp_disable' => TRUE,
     ), TRUE);
     $this->casHelper->log("Gateway activated, redirecting to $cas_login_url");
-    $event->setResponse(RedirectResponse::create($cas_login_url));
+    $event->setResponse(TrustedRedirectResponse::create($cas_login_url));
 
     return TRUE;
   }
diff --git a/tests/src/Unit/Controller/ForceLoginControllerTest.php b/tests/src/Unit/Controller/ForceLoginControllerTest.php
index 520dd2b..3250aad 100644
--- a/tests/src/Unit/Controller/ForceLoginControllerTest.php
+++ b/tests/src/Unit/Controller/ForceLoginControllerTest.php
@@ -8,7 +8,7 @@
 namespace Drupal\Tests\cas\Unit\Controller;
 
 use Drupal\Tests\UnitTestCase;
-use Symfony\Component\HttpFoundation\RedirectResponse;
+use Drupal\Core\Routing\TrustedRedirectResponse;
 use Drupal\cas\Controller\ForceLoginController;
 
 /**
@@ -69,7 +69,7 @@ class ForceLoginControllerTest extends UnitTestCase {
       ->with($this->equalTo($parameters))
       ->will($this->returnValue('https://example.com'));
 
-    $expected_response = new RedirectResponse('https://example.com', 302);
+    $expected_response = new TrustedRedirectResponse('https://example.com', 302);
 
     $force_login_controller = new ForceLoginController($this->casHelper, $this->requestStack);
     $response = $force_login_controller->forceLogin();
diff --git a/tests/src/Unit/Controller/LogoutControllerTest.php b/tests/src/Unit/Controller/LogoutControllerTest.php
index b4ecc69..4231091 100644
--- a/tests/src/Unit/Controller/LogoutControllerTest.php
+++ b/tests/src/Unit/Controller/LogoutControllerTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\Tests\cas\Unit\Controller;
 
 use Drupal\Tests\UnitTestCase;
-use Symfony\Component\HttpFoundation\RedirectResponse;
 use Drupal\cas\Controller\LogoutController;
 
 /**
diff --git a/tests/src/Unit/Subscriber/CasSubscriberTest.php b/tests/src/Unit/Subscriber/CasSubscriberTest.php
index 873ebc3..8728e2a 100644
--- a/tests/src/Unit/Subscriber/CasSubscriberTest.php
+++ b/tests/src/Unit/Subscriber/CasSubscriberTest.php
@@ -14,7 +14,6 @@ use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\ServerBag;
 use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Session\AccountInterface;
-use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\HttpKernelInterface;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;