<?php require __DIR__ . '/../config.php'; $pdo=get_pdo(); $contact=intval($_GET['cid']??0); $token=$_GET['token']??''; $conf=get_config(); if(md5($contact.$conf['unsubscribe_secret'])!=$token){echo 'Invalid';exit;} $pdo->prepare('UPDATE list_contacts SET unsubscribed=0 WHERE id=?')->execute([$contact]); echo 'Subscription confirmed';