Curl - Load a Site with Cloudflare Protection

cURL - Load a site with CloudFlare protection

That would be CloudFlare's I'm Under Attack Mode --> http://blog.cloudflare.com/introducing-im-under-attack-mode

If you are the owner of the site you should whitelist your own IP address. If you're a visitor to the site either

1.) The website owner has the feature enabled on their own website in which case it's intentional and there is no way around that as they are protecting their website or

2.) You are loading the site too often -- and you're triggering CloudFlare's DDOS protection.

p.s. Disclaimer: I work for CloudFlare.

Where does CloudFlare detect web and terminal requests?! On equal terms

Cloudflare uses various techniques to determine whether the user agent is a real browser or not. And, the site owner can also determine the level of risk they can allow via the Cloudflare platform.

Let's discuss a few techniques (I know) used by Cloudflare:

1. TLS fingerprinting
   This is one of the prominent techniques used notoriously by Cloudflare. This is also the reason why tools like native proxy are popular. Link: https://github.com/klzgrad/naiveproxy

2. Cookies
   Cloudflare used to have some cf_ related cookies which are used to distinguish real users or not.

And, these are only a few techniques. Cloudflare has many more.

And, this issue is not just limited to Cloudflare, China firewall is also notorious for using such modus operandi to distinguish various things.

curl: can't fetch rss from website because of CloudFlare

You can't easily bypass Cloudflare. However you can hack the protection system. :)

First, parse the page (Cloudflare protection page) and calculate 3+13*7 (most probably this will be different for each request.) in

$(function(){setTimeout(
            function(){
                $('#jschl_answer').val(3+13*7);
                $('#ChallengeForm').submit();
            },
            5850
)});

Then send post request the same page with "jschl_vc" value from #ChallengeForm which you got from parsed data and "jschl_answer" value as 3+13*7. And then try to fetch the page again with the cookie value that Cloudflare added. When you're added Cloudflare whitelist, you won't see that page anymore.

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