Fix/367 Bypass Vulnerability Fix

[bmarshall511]

Description of the Change

Addresses https://patchstack.com/database/report-preview/c3c10882-9241-4bc3-a589-29f743bcf494?pin=nOv31SVbrrIdLYDH

Closes #367

How to test the Change

Get yourself banned in any ways, like posting tons of comments. You should see a 'Your IP has been flagged as spam/malicious'. Then make another comment and this time, add ?anything.ico in the url.

Go to http://127.0.0.1/wordpress/wp-admin/options-general.php?page=wordpress-zero-spam-settings&subview=settings and add an ip entry in the ip address whitelist, like 127.0.0.1. Get yourself banned by any means allowed by the plugin. Make another request, but this time, add a X-Forwarded-For header with the value 127.0.0.1

Changelog Entry

Security - Vulnerability: Fixed bypass methods for blocked IP addresses

Credits

Props @bmarshall511

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.