diff --git a/core/Controller/LoginController.php b/core/Controller/LoginController.php
index 5db650c4c47a487eb01b8ad3bf16aac1c8f211b8..09b6fe54384b4a32b93c9141ba680d72514b941d 100644
--- a/core/Controller/LoginController.php
+++ b/core/Controller/LoginController.php
@@ -382,7 +382,7 @@ class LoginController extends Controller {
 		$response = new RedirectResponse(
 			$this->urlGenerator->linkToRoute('core.login.showLoginForm', $args)
 		);
-		$response->throttle(['user' => $user]);
+		$response->throttle(['user' => substr($user, 0, 64)]);
 		$this->session->set('loginMessages', [
 			[$loginMessage], []
 		]);