page fingerprint differential detected -possible local file include

The scanner is seeing page content that is different than what is expected: fingerprint differential

The scanner is suggesting there could be an include or require statement inserted that brings in arbitrary code from another file on your server: possible local file include

The page you posted appears to be an error page, so the scanner may have made a bad request or was blocked by some security protocol. That would explain the “fingerprint differential”. It’s probably a false alarm, but let’s assume for now that it’s not.

If you added some custom code relating to the page, there may be no cause for concern. Even if you just opened a file, then saved it again without making any changes, that could change the fingerprint “seen” by the scanner. Otherwise it could mean you’ve been hacked and your site is serving undesirable content.

You need to independently confirm there’s a real issue before reacting to a possible hacking. Try some other online scanners. Carefully examine the page source HTML for content that does not belong. View the page as different users or not logged in to check for conditional content. Also try using the “fetch as Googlebot” tool in the site’s Google Search Console (webmaster tools) to be sure there’s not “special” content just for search bots.