diff --git a/lib/private/legacy/OC_User.php b/lib/private/legacy/OC_User.php
index e5343864c4585..1f2f159d52b1d 100644
--- a/lib/private/legacy/OC_User.php
+++ b/lib/private/legacy/OC_User.php
@@ -294,7 +294,10 @@ public static function getLogoutUrl(\OCP\IURLGenerator $urlGenerator) {
 		if ($user instanceof IUser) {
 			$backend = $user->getBackend();
 			if ($backend instanceof \OCP\User\Backend\ICustomLogout) {
-				return $backend->getLogoutUrl();
+				$logoutUrl = $backend->getLogoutUrl();
+				if ($logoutUrl !== '') {
+					return $logoutUrl;
+				}
 			}
 		}