Re: Possible query problem
| From: | Chris Shiflett | Date: | Tue, 28 Oct 2003 17:10:02 +0000 |
| Subject: | Re: Possible query problem | ||
| References: | 1 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-167893@lists.php.net to get a copy of this message | ||
I didn't look into your problem, but I want to mention one thing that stands
out to me.
--- Frank Tudor <frank_tudor@yahoo.com> wrote:
> $query="SELECT payment FROM payment WHERE
> dln='".$_POST["dln"]."' =
> payment.dln='".$_POST["dln"]."' and
> users.password='".$_POST["password"]."'";
Never, ever build an SQL query using data directly from the client. You place
yourself at the mercy of every user of your site and their creative potential.
This code constitutes a security vulnerability.
Filter all data, assign it to another variable (so you know it has been
filtered), and then build your query using the filtered data:
$clean['dln'] = '';
if ($_POST['dln'] looks like a valid value)
{
$clean['dln'] = $_POST['dln'];
}
$sql = "... {$clean['dln']} ...";
Something similar to that anyway.
Hope that helps.
Chris
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