CWE-293 Using Referer Field for Authentication

The referer field in HTTP requests can be easily modified and, as such, is not a valid means of message integrity checking.

• Access Control: Gain Privileges or Assume Identity — Actions, which may not be authorized otherwise, can be carried out as if they were validated by the server referred to.

• [Architecture and Design] In order to usefully check if a given action is authorized, some means of strong authentication and method protection must be used. Use other means of authorization that cannot be simply spoofed. Possibilities include a username/password or certificate.

• Automated Static Analysis: Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)