Transport Layer Security (TLS) provides secure communication between systems over the internet by encrypting the data sent between them. In this process, the role of hostname validation, combined with certificate validation, is to ensure that a system is indeed the one it claims to be, adding an extra layer of trust and security. When hostname validation is disabled, the client skips this critical check. This creates an opportunity for attackers to pose as a trusted entity and intercept, manipulate, or steal the data being transmitted. To do so, an attacker would obtain a valid certificate authenticating `example.com`, serve it using a different hostname, and the application code would still accept it.