Question

How would you secure a slug in Symfony2.1?

A malicious user could append ";rm -rf *" to the id value and delete the entire Website. In symfony2.1, is there a simple way to secure the slugs?

I have tried to secure an id this way.

/**
 * The idea is to check that the slug cart_id is an id and not
 *
 * @Route("/{cart_id}/show", name="show_cart")
 * @Template()
 */
public function showCartAction($cart_id)
{

    if (!preg_match("/^[0-9]{2}$/", $cart_id))
    {
       throw new \Exception("the id is not correct");
    }

    $cart = $this->getCartManager()
        ->getCart($cart_id);

    return array(
        'cart'=> cart
    );
}

Do you find this necessary? Would you do it this way ?

Answer 1

You can ensure that cart_id will always accept integer by adding requirements in @Route annotation. e.g

/**
 * @Route("/{cart_id}/show", name="show_cart", requirements={"cart_id" = ("\d+")})
 * @Template()
 */

But still there is almost zero chance that the attacker will execute malicious query via sql-injection as Doctrine2 uses PDO prepared statement with parametarized query. For more information about prepared statement with parametarized query see here and here.