KN Fix Your Title <= 1.0.1 - Authenticated Stored XSS
The plugin was vulnerable to Authenticated Stored XSS in the separator field.
Proof of Concept
1. Install WordPress 5.7.2
2. Install and activate KN Fix Your Title
3. Navigate to Fix Title under Settings Tab >> Click on I have done this and enter the XSS payload into the Separator input field.
4. Click Save Changes.
6. Payload Used: "><script>alert(document.cookie)</script>