向服务器发送请求时伪造User-Agent？

Question

I am reading Detecting Device Type in a web application and just got curious if it would be possible to client to fake the User-Agent when sending the request?

Question(s)
- user sends request via curl command but fakes it to look as if request is coming from Mobile on the server? is it possible?
- Can server detect it?
- Can server prevent it?

Thanks

Answer 1

It is possible and easy. All you have to do is set the user-agent header string. I've seen a browser that allowed you to set it (don't remember which one). On the server it is very hard to know. A lot of bots pretend to be a browser so they don't get filtered out.