diff --git a/lib/private/User/Session.php b/lib/private/User/Session.php
index 6b97f8925c331..7c3bcb95d9740 100644
--- a/lib/private/User/Session.php
+++ b/lib/private/User/Session.php
@@ -914,9 +914,10 @@ public function loginWithCookie($uid, $currentToken, $oldSessionId) {
 			]);
 			return false;
 		} catch (InvalidTokenException $ex) {
-			$this->logger->error('Renewing session token failed', [
+			$this->logger->error('Renewing session token failed: ' . $ex->getMessage(), [
 				'app' => 'core',
 				'user' => $uid,
+				'exception' => $ex,
 			]);
 			return false;
 		}