I manage a website which is being "attacked" by a very stupid bot. The bot tries the same requests all the time, it always gets a bad request response because ASP.NET detects "A potentially dangerous Request.Path value was detected from the client".
I tried to add the bot's IP to my denied ips via IIS/Web.config (ipSecurity)/.htaccess file (Helicon ape), in general it works and blocks the ip from "normal" requests. But when the bot tries to access its weird urls like 'mydomain.com/a.aspx/+[PLM=0]+GET+http://bla.bla.com' the servers throws an exception: System.Web.HttpException: A potentially dangerous Request.Path value was detected from the client (:).
I don't want my weak server to even try process any request from that IP, certainly not throwing exceptions all the time. The server is on a shared host so I don't have many options like adding some router like fortinet etc. that will block the IP at a lower level.
Any idea how can I convince my server to always ignore requests from those specific IPs, even when it tries the potentially dangerous requests? Any other suggestions how to handle this situation?