This is not an Issue. It's more to a feature request , specially about rlm_rest. Currently I Always use 'POST' method with JSON body. I did this because my FreeRadius installation need to serve different kind of Radius client, that each client send different set of attribute. For example a single Mikrotik router that act as a VPN server and A Captive portal (they name it "hotspot". Each of it sent different set of attribute. my only concern is that a creating a http backend that handle a post request need to allow XSRF at first and make a second step to validate if request come from allowed host. So I think it'll be great if rlm_rest have an option that use GET method that encode all attributes as query parameters. Thats all My salute to all FreeRadius developers and contributors