diff --git a/auth.php b/auth.php
index c891d3d..8563cbf 100644
--- a/auth.php
+++ b/auth.php
@@ -139,7 +139,7 @@ class auth_plugin_jwt extends auth_plugin_base {
     public function user_login_jwt() {
         global $SESSION, $CFG, $USER;
 
-        $keyvalue = required_param('key', PARAM_ALPHANUM);
+        $keyvalue = required_param('key', PARAM_RAW);
         $wantsurl = optional_param('wantsurl', '', PARAM_URL);
 
         if (!empty($wantsurl)) {