The vulnerability is due to a missing capability check in a function within the plugin called wpforms_is_admin_page, which means that the plugin doesn’t check for appropriate permissions of the user attempting to make a change with this function. That means that the plugin allows data to be modified by attackers lacking sufficient privileges.
Recommendations:
It’s recommended that users of versions WPForms plugin users from versions 1.8.4 up to an including 1.9.2.1 update their plugins.
Source: WPForms Plugin Vulnerability Affects Up To 6 Million Sites