Cross-site request forgery (CSRF) vulnerability in the administration console in TP-Link TL-WR840N (V1) router with firmware before 3.13.27 build 141120 allows remote attackers to hijack the authentication of administrators for requests that change router settings via a configuration file import.
The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.