diff --git a/captcha.inc b/captcha.inc
index 86b6a00..f19cef4 100644
--- a/captcha.inc
+++ b/captcha.inc
@@ -109,7 +109,7 @@ function _captcha_generate_captcha_session($form_id=NULL, $status=CAPTCHA_STATUS
   // Insert an entry and thankfully receive the value of the autoincrement field 'csid'.
   $captcha_sid = db_insert('captcha_sessions')
   ->fields(array(
-    'uid' => $user->uid,
+    'uid' => $user->id(),
     'sid' => session_id(),
     'ip_address' => Drupal::request()->getClientIp(),
     'timestamp' => REQUEST_TIME,
diff --git a/image_captcha/image_captcha.module b/image_captcha/image_captcha.module
index d16e5a4..7ff445c 100644
--- a/image_captcha/image_captcha.module
+++ b/image_captcha/image_captcha.module
@@ -232,7 +232,7 @@ function image_captcha_captcha($op, $captcha_type='', $captcha_sid=NULL) {
         // for the image itself won't succeed (only ?q=user is permitted for
         // unauthenticated users). We fall back to the Math CAPTCHA in that case.
         global $user;
-        if (variable_get('maintenance_mode', 0) && $user->uid == 0) {
+        if (variable_get('maintenance_mode', 0) && $user->id() == 0) {
           return captcha_captcha('generate', 'Math');
         }
         // generate a CAPTCHA code