The bLoyal: Loyalty & Promotions by bLoyal plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 3.1.611.78. This is due to the AJAX actions `save_bloyal_configuration_data` and `save_bloyal_accesskeyverification_data` being registered without any capability or nonce checks, and the `bloyal_customer_auto_login` function unconditionally trusting the `Customer.ExternalId` value returned by whichever API URL is stored in the plugin's options. This makes it possible for authenticated attackers, with Subscriber-level access and above, to overwrite the plugin's bLoyal Loyalty Engine API URL (`bloyal_custom_loyaltyengine_api_url`) and the `is_bloyal_custom_api_url` flag via the unprotected AJAX actions, then trigger the unauthenticated `/cart` REST route to cause `bloyal_customer_auto_login` to fetch customer data from an attacker-controlled endpoint and call `wp_set_auth_cookie()` with an attacker-supplied `Customer.ExternalId`, thereby authenticating as any WordPress user including the site Administrator.
Attack Parameters
Impact Assessment
CVSS Vector v3.1