modules/security/classes/general.post_filter.php/post_filter.php in the Web Application Firewall in Bitrix24 through 20.0.950 allows XSS by placing %00 before the payload.
- https://blog.deteact.com/bitrix-waf-bypass/
- https://github.com/20142995/nuclei-templates
- https://github.com/cyb3r-w0lf/nuclei-template-collection