$key = wp_hash($username . $pass_frag . '|' . $expiration, $scheme);
$hash = hash_hmac('md5', $username . '|' . $expiration, $key);
- if ( $hmac != $hash ) {
+ if ( hash_hmac( 'md5', $hmac, $key ) !== hash_hmac( 'md5', $hash, $key ) ) {
do_action('auth_cookie_bad_hash', $cookie_elements);
return false;
}