A improper neutralization of input during web page generation ('cross-site scripting') in Fortinet FortiWeb version 6.4.1 and 6.4.0, version 6.3.15 and below, version 6.2.6 and below allows attacker to execute unauthorized code or commands via crafted HTTP GET requests to the login webpage.

A unintended proxy or intermediary ('confused deputy') in Fortinet FortiWeb version 6.4.1 and below, 6.3.15 and below allows an unauthenticated attacker to access protected hosts via crafted HTTP requests.

A url redirection to untrusted site ('open redirect') in Fortinet FortiWeb version 6.4.1 and below, 6.3.15 and below allows attacker to use the device as proxy via crafted GET parameters in requests to error handlers

A url redirection to untrusted site ('open redirect') in Fortinet FortiWeb version 6.4.1 and 6.4.0, version 6.3.15 and below, version 6.2.6 and below allows attacker to use the device as a proxy and reach external or protected hosts via redirection handlers.