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Re: Can server tell I'm using curl?

From: Dan Fandrich via curl-users <>
Date: Tue, 6 Apr 2021 13:57:56 -0700

On Tue, Apr 06, 2021 at 01:37:42PM +0200, Gilles via curl-users wrote:
> Is the command wrong, or is the server somehow able to tell I'm using curl to
> forbid its use

I've heard that some sites check things like the order of headers being sent as
well as various HTTP/2 options and even use TCP fingerprinting to try to ferret
out robots masquerading as browsers. curl can't hide itself from sites doing
that sort of client detection, but fortunately, that seems to be rare.

Received on 2021-04-06