If you're creating an application that displays URLs to users (chat app for example), please make sure to apply spoof checks to avoid use of UTF-8 confusables in IDN homograph attacks. You may want to

If you're creating an application that displays URLs to users (chat app for example), please make sure to apply spoof checks to avoid use of UTF-8 confusables in IDN homograph attacks. You may want to block URLs with hostnames that get flagged, or display them in #punycode instead.

As an example, see https://github.com/chromium/chromium/tree/main/components/url_formatter/spoof_checks

In particular https://github.com/chromium/chromium/blob/8e070073d47861b8bfc7548dce8fcfc708a356fb/components/url_formatter/spoof_checks/idn_spoof_checker.cc#L177 is quite interesting read.

#cybersecurity #infosec