Taint
Instalação/Configuração
Taint
PHP Manual

# Introdução

Taint is an extension, which is used for detecting XSS codes(tainted string). And also can be used to spot sql injection vulnerabilities, and shell inject, etc.

When taint is enabled, if you pass a tainted string (comes from $_GET, $_POST or $_COOKIE) to some functions, taint will warn you about that.

Exemplo #1 Taint()example

`<?php
$a = trim($_GET['a']);
$file_name = '/tmp' . $a;
$output = "Welcome, {$a} !!!";
$var = "output";
$sql = "Select * from " . $a;
$sql .= "ooxx";
echo $output;
print $$var;
include($file_name);
mysql_query($sql);
?>`

O exemplo acima irá imprimir algo similar à:

    Warning: main() [function.echo]: Attempt to echo a string that might be tainted

    Warning: main() [function.echo]: Attempt to print a string that might be tainted

    Warning: include() [function.include]: File path contains data that might be tainted

    Warning: mysql_query() [function.mysql-query]: SQL statement contains data that might be tainted

Taint
Instalação/Configuração
Taint
PHP Manual