title: Laravel : The payload is invalid
body: <p>I've upgraded 2 laravel applications on 5.4 few months ago.</p>
  
  <p>Those application were created on 5.1, and I've always follow the upgrade guide 1 month after any release publication.</p>
  
  <p>Since 5.4, I often have this kind of error on POST request :</p>
  
  <pre><code>Illuminate\Contracts\Encryption\DecryptException·The payload is invalid
  
  
  app/Http/Middleware/CheckForMaintenanceMode.php:43App\Http\Middleware\CheckForMaintenanceMode::handle   
           throw new HttpException(503);
      }
      return $next($request); //line 43
  }}
  </code></pre>
  
  <p>Most of the time POST request are ok, but sometimes (around 1 POST request on 1000) I have this error. I fail to reproduce it.</p>
  
  <p>Thanks</p>