modified regex for url validation

app/Http/Controllers/SettingsController.php

@@ -290,8 +290,8 @@ class SettingsController extends Controller
             $blacklist = substr($blacklist, 0, stripos($blacklist, '/'));
         }
 
-        $regexUrl = '#^(\*\.)?[a-z0-9.]*$#';
-        if(preg_match($regexUrl, $blacklist) == 1){
+        $regexUrl = '#^[a-z0-9]+(\.[a-z0-9]{2,})+$#';
+        if(preg_match($regexUrl, $blacklist) === 1){
 
             $path = \Request::path();
             $cookiePath = "/" . substr($path, 0, strpos($path, "meta/") + 5);