index.php file has been reported by Configsever exploit scanner

It appears your site is hacked. WordPress’s main index.php file should look something like this:

<?php
/**
 * Front to the WordPress application. This file doesn't do anything, but loads
 * wp-blog-header.php which does and tells WordPress to load the theme.
 *
 * @package WordPress
 */

/**
 * Tells WordPress to load the WordPress theme and output it.
 *
 * @var bool
 */
define( 'WP_USE_THEMES', true );

/** Loads the WordPress Environment and Template */
require __DIR__ . '/wp-blog-header.php';

If you have a pristine backup taken before the hack, simply nuke the current site and restore the pristine backup. If you don’t have such a backup, kindly read this documentation thoroughly to find to how to properly clean up your site:

FAQ My site was hacked

After this, follow the guide below to find out how to properly secure and harden your website to thwart future attacks:

Hardening WordPress

This could be a false positive then.

I’ll advise you to contact the ConfigServer folks so they can look into this. Back when I managed cPanel servers I used their products and they had outstanding support.