curl / Mailing Lists / curl-users / Single Mail
Buy commercial curl support from WolfSSL. We help you work out your issues, debug your libcurl applications, use the API, port to new platforms, add new features and more. With a team lead by the curl founder himself.

Strange redirection to Cloudflare server with Captcha?

From: Mac-Fly via curl-users <>
Date: Sat, 15 May 2021 05:19:44 +0200

Dear all,

since a few days a have the problem that a few pages that used to work just fine now return a page that comes from Cloudflare and wants to input some Captcha.

For example, a call to:
...returns a webpage with the title:
<title>Please Wait... | Cloudflare</title>
...and this meta-data:
<meta name="captcha-bypass" id="captcha-bypass" />
...and of course more content.
Strangely the same page called form any browser works just fine. And also, _was_ working fine for ages!
Also I tried to set the user agent to be exactly as my browser with no effect.

Do you have any idea what this may cause and (more important) how to work-around? :-)

The cURL I am using is:
curl 7.76.1 (i386-pc-win32) libcurl/7.76.1 OpenSSL/1.1.1k (Schannel) zlib/1.2.11 brotli/1.0.9 zstd/1.4.9 WinIDN libssh2/1.9.0 nghttp2/1.43.0 libgsasl/1.10.0

Received on 2021-05-15