HttpClient will Encode the url internally

Question

Here is my link:

58.87.64.22/?{{%25}}cake\=1

When I open it in Chrome, it will give me 400 status code which is correct.

But When I open it using HTTP client, it will return 200 status code:

HttpClient client = new HttpClient();
var w = await client.GetAsync("http://58.87.64.22/?{{%25}}cake\\=1");

it seems HTTP client will encode the URL into this:

58.87.64.22/?%7B%7B%25%7D%7Dcake%5C=1

when I test the encoded URL in Chrome, it will open a webpage and will return 200 status code.

How to solve such a thing? I need to get 400 status code when sending request to this URL.

Answer 1

Pass a Uri object instantiated via the overload having a UriCreationOptions argument with DangerousDisablePathAndQueryCanonicalization set to true.

Gets or sets a value that indicates whether the path and query are validated and normalized.
true to disable path and query validation; false to enable it.

var options = new UriCreationOptions 
{
    DangerousDisablePathAndQueryCanonicalization = true
};
var uri = new Uri(@"http://58.87.64.22/?{{%25}}cake\=1", options);

HttpClient client = new HttpClient();
await client.GetAsync(uri);

---

Fiddler shows that below request is being made without any encoding.

GET http://58.87.64.22/?{{%25}}cake\=1 HTTP/1.1
Host: 58.87.64.22

Resulting in a Bad Request HTTP status code.

HTTP/1.1 400