diff --git a/core/modules/system/src/Tests/System/AccessDeniedTest.php b/core/modules/system/src/Tests/System/AccessDeniedTest.php
index 5c6c3bf..f3cc0e0 100644
--- a/core/modules/system/src/Tests/System/AccessDeniedTest.php
+++ b/core/modules/system/src/Tests/System/AccessDeniedTest.php
@@ -23,7 +23,7 @@ class AccessDeniedTest extends WebTestBase {
    *
    * @var array
    */
-  public static $modules = ['block'];
+  public static $modules = ['block', 'node'];
 
   protected $adminUser;
 
@@ -109,4 +109,14 @@ function testAccessDenied() {
     // Check that we're still on the same page.
     $this->assertText(t('Basic site settings'));
   }
+
+  public function testAccessDeniedCustomPageWithAccessDenied() {
+    // Sets up a 404 page not accessible by the anonymous user.
+    $this->config('system.site')->set('page.403', '/admin/index')->save();
+
+    $this->drupalGet('/admin');
+    $this->assertNoText('Administration');
+    $this->assertResponse(403);
+  }
+
 }
diff --git a/core/modules/system/src/Tests/System/PageNotFoundTest.php b/core/modules/system/src/Tests/System/PageNotFoundTest.php
index b7c0609..2632d7d 100644
--- a/core/modules/system/src/Tests/System/PageNotFoundTest.php
+++ b/core/modules/system/src/Tests/System/PageNotFoundTest.php
@@ -50,4 +50,14 @@ function testPageNotFound() {
     $this->drupalGet($this->randomMachineName(10));
     $this->assertText($this->adminUser->getUsername(), 'Found the custom 404 page');
   }
+
+  public function testAccessDeniedCustomPageWithAccessDenied() {
+    // Sets up a 404 page not accessible by the anonymous user.
+    $this->config('system.site')->set('page.404', '/admin/index')->save();
+
+    $this->drupalGet('/admin');
+    $this->assertNoText('Administration');
+    $this->assertResponse(403);
+  }
+
 }