Patent ID: 8429751

Claim:
A method for securing a web server, the method comprising: tokenizing, with a processor, a referrer domain name from an HTTP header of a received HTTP request to form a set of referrer tokens, each token of the set of referrer tokens representing a portion of the referrer domain name; tokenizing, with the processor, a host domain name from the HTTP header to form a set of host tokens, each token of the set of host tokens representing a portion of the host domain name; comparing at least two referrer tokens of the set of referrer tokens to at least two host tokens of the set of host tokens, the at least two referrer tokens including a first top level domain token, the at least two host tokens including a second top level domain token; determining whether the received request is a result of an instruction from an external source based on whether the at least two referrer tokens match the at least two host tokens; and performing a responsive action if the request is the result of the instruction from the external source.