Disclosed are various embodiments for validating the identity of network sites. A communication session is established with a network site using a credential for the network site. A validation of the communication session is generated based at least in part upon a profile for the network site. The profile is derived from at least one previous communication session with the network site. An action is initiated in response to the validation when the validation indicates a discrepancy exists between the profile for the network site and the communication session with the network site.