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mysqlwordpresssecuritysql-injection

Does using the WordPress get_results() database function prevent sql injection


Couldn't seem to find a answer but wondering if the following query to the database is vulnerable to sql injection.

$searchPostResults = $wpdb->get_results($querySearchVals, OBJECT);

This is the query which is used:

global $wpdb;
$offset = (isset($_POST["moreSearchResults"])) ? $_POST["searchOffset"] : 0;

$querySearchVals = "
    SELECT DISTINCT post_title, ID
    FROM {$wpdb->prefix}posts
    WHERE (";

$sVals = array();
$sVals = explode(" ", $searchVal);

$lastIndex = intval(count($sVals)) - 1;
$orderByCaseVals = "";
for($i = 0; $i<count($sVals);$i++)
{
    $querySearchVals .= " post_title LIKE '%$sVals[$i]%' ";
    if($i != $lastIndex)
        $querySearchVals .= " OR ";

    $orderByCaseVals .= " WHEN post_title LIKE '%$sVals[$i]%' THEN ($i + 2) ";
}

$querySearchVals .= ") 
    AND {$wpdb->prefix}posts.post_type = 'post'
    AND post_status = 'publish' 
    ORDER BY CASE
        WHEN post_title LIKE '%$searchVal%' THEN 1
        $orderByCaseVals
    END
    LIMIT $offset, 6;
";

Cheers


Solution

  • Ok so as tadman explained the get_results does not prevent the sql injection attack.

    the prepare function needs to be used.

    I have re written the above code to prevent sql injection:

    global $wpdb;
    $offset = (isset($_POST["moreSearchResults"])) ? $_POST["searchOffset"] : 0;
    
    $querySearchVals = "
        SELECT DISTINCT post_title, ID
        FROM {$wpdb->prefix}posts
        WHERE (";
    
    $sVals = array();
    $sVals = explode(" ", $searchVal);
    
    $lastIndex = intval(count($sVals)) - 1;
    $orderByCaseVals = "";
    for($i = 0; $i<count($sVals);$i++)
    {
        $queryPrep = $wpdb->prepare(" post_title LIKE '%%%s%%' ", $wpdb->esc_like( $sVals[$i] ));
        $querySearchVals .= $queryPrep;
        if($i != $lastIndex)
            $querySearchVals .= " OR ";
    
        $queryPrep = $wpdb->prepare(" WHEN post_title LIKE '%%%s%%' THEN ($i + 2) ", $wpdb->esc_like( $sVals[$i] ));
        $orderByCaseVals .= $queryPrep;
    }
    
    $querySearchVals .= ") 
        AND {$wpdb->prefix}posts.post_type = 'post'
        AND post_status = 'publish' 
        ORDER BY CASE";
    
    $queryPrep = $wpdb->prepare(" WHEN post_title LIKE '%%%s%%' THEN 1 ", $wpdb->esc_like( $searchVal ));
    $querySearchVals .= $queryPrep;
    $querySearchVals .= "
            $orderByCaseVals
        END
    ";
    
    $queryPrep = $wpdb->prepare(" LIMIT %d, 12", $offset);
    $querySearchVals .= $queryPrep . ";";