If your application fetches data from external sources, maintain a strict allowlist of approved domains or IP addresses. Any request pointing to localhost , 127.0.0.1 , or local file paths should be instantly dropped and logged as a security event.
The prefix is a URI (Uniform Resource Identifier) scheme used to access files on one’s own computer or local network, rather than a remote server (which would use http:// or https:// ). 2. The Context: The "Fetch" API fetch-url-file-3A-2F-2F-2F
The lack of support in browsers and the cautious approach in Node.js all comes down to one thing: . If your application fetches data from external sources,