diff --git a/core/modules/field_ui/lib/Drupal/field_ui/Access/ViewModeAccessCheck.php b/core/modules/field_ui/lib/Drupal/field_ui/Access/ViewModeAccessCheck.php
index 2fe350b..95d78fa 100644
--- a/core/modules/field_ui/lib/Drupal/field_ui/Access/ViewModeAccessCheck.php
+++ b/core/modules/field_ui/lib/Drupal/field_ui/Access/ViewModeAccessCheck.php
@@ -47,6 +47,8 @@ public function access(Route $route, Request $request, AccountInterface $account
         return $account->hasPermission($permission) ? static::ALLOW : static::DENY;
       }
     }
+
+    return static::DENY;
   }
 
 }
diff --git a/core/modules/node/lib/Drupal/node/Access/NodeRevisionAccessCheck.php b/core/modules/node/lib/Drupal/node/Access/NodeRevisionAccessCheck.php
index 096335f..02ab949 100644
--- a/core/modules/node/lib/Drupal/node/Access/NodeRevisionAccessCheck.php
+++ b/core/modules/node/lib/Drupal/node/Access/NodeRevisionAccessCheck.php
@@ -136,7 +136,7 @@ public function checkAccess(NodeInterface $node, AccountInterface $account, $op
     if (!isset($this->access[$cid])) {
       // Perform basic permission checks first.
       if (!user_access($map[$op], $account) && !user_access($type_map[$op], $account) && !user_access('administer nodes', $account)) {
-        return $this->access[$cid] = FALSE;
+        $this->access[$cid] = FALSE;
       }
 
       // There should be at least two revisions. If the vid of the given node
diff --git a/core/modules/tracker/lib/Drupal/tracker/Access/ViewOwnTrackerAccessCheck.php b/core/modules/tracker/lib/Drupal/tracker/Access/ViewOwnTrackerAccessCheck.php
index 18498f9..11f42c1 100644
--- a/core/modules/tracker/lib/Drupal/tracker/Access/ViewOwnTrackerAccessCheck.php
+++ b/core/modules/tracker/lib/Drupal/tracker/Access/ViewOwnTrackerAccessCheck.php
@@ -30,7 +30,7 @@ public function appliesTo() {
   public function access(Route $route, Request $request, AccountInterface $account) {
     // The user object from the User ID in the path.
     $user = $request->attributes->get('user');
-    return $user && $account->isAuthenticated() && ($user->id() == $account->id());
+    return ($user && $account->isAuthenticated() && ($user->id() == $account->id())) ? static::ALLOW : static::DENY;
   }
 }