You can find Basic authentication mechanism using this tool.
HTTP basic authentication represents a mechanism of challenge and response to help the server make a request authentication from a client, passing the User ID and password in the URL as the standard HTTP “Authorization” header. For example: https://username:[email protected]/example-page.php.
If remote web server contains web pages that are protected by 'Basic' authentication over cleartext, an attacker eavesdropping the traffic might obtain logins and passwords of valid users.
Make sure that HTTP authentication is transmitted over HTTPS.