How to Protect WordPress Against Malicious URL Requests

Are you looking for a way to protect your WordPress site form malicious URL requests? While there’s probably a plugin for this, we have created a quick code snippet that you can use to protect WordPress against malicious URL requests in WordPress.

Instructions:

All you have to do is add this code to your theme’s .htaccess file.

$request_uri = $_SERVER['REQUEST_URI'];
$query_string = $_SERVER['QUERY_STRING'];
$user_agent = $_SERVER['HTTP_USER_AGENT'];

// request uri
if (	//strlen($request_uri) > 255 || 
	stripos($request_uri, 'eval(') || 
	stripos($request_uri, 'CONCAT') || 
	stripos($request_uri, 'UNION+SELECT') || 
	stripos($request_uri, '(null)') || 
	stripos($request_uri, 'base64_') || 
	stripos($request_uri, '/localhost') || 
	stripos($request_uri, '/pingserver') || 
	stripos($request_uri, '/config.') || 
	stripos($request_uri, '/wwwroot') || 
	stripos($request_uri, '/makefile') || 
	stripos($request_uri, 'crossdomain.') || 
	stripos($request_uri, 'proc/self/environ') || 
	stripos($request_uri, 'etc/passwd') || 
	stripos($request_uri, '/https/') || 
	stripos($request_uri, '/http/') || 
	stripos($request_uri, '/ftp/') || 
	stripos($request_uri, '/cgi/') || 
	stripos($request_uri, '.cgi') || 
	stripos($request_uri, '.exe') || 
	stripos($request_uri, '.sql') || 
	stripos($request_uri, '.ini') || 
	stripos($request_uri, '.dll') || 
	stripos($request_uri, '.asp') || 
	stripos($request_uri, '.jsp') || 
	stripos($request_uri, '/.bash') || 
	stripos($request_uri, '/.git') || 
	stripos($request_uri, '/.svn') || 
	stripos($request_uri, '/.tar') || 
	stripos($request_uri, ' ') || 
	stripos($request_uri, '<') || 
	stripos($request_uri, '>') || 
	stripos($request_uri, '/=') || 
	stripos($request_uri, '...') || 
	stripos($request_uri, '+++') || 
	stripos($request_uri, '://') || 
	stripos($request_uri, '/&&') || 
	// query strings
	stripos($query_string, '?') || 
	stripos($query_string, ':') || 
	stripos($query_string, '[') || 
	stripos($query_string, ']') || 
	stripos($query_string, '../') || 
	stripos($query_string, '127.0.0.1') || 
	stripos($query_string, 'loopback') || 
	stripos($query_string, '%0A') || 
	stripos($query_string, '%0D') || 
	stripos($query_string, '%22') || 
	stripos($query_string, '%27') || 
	stripos($query_string, '%3C') || 
	stripos($query_string, '%3E') || 
	stripos($query_string, '%00') || 
	stripos($query_string, '%2e%2e') || 
	stripos($query_string, 'union') || 
	stripos($query_string, 'input_file') || 
	stripos($query_string, 'execute') || 
	stripos($query_string, 'mosconfig') || 
	stripos($query_string, 'environ') || 
	//stripos($query_string, 'scanner') || 
	stripos($query_string, 'path=.') || 
	stripos($query_string, 'mod=.') || 
	// user agents
	stripos($user_agent, 'binlar') || 
	stripos($user_agent, 'casper') || 
	stripos($user_agent, 'cmswor') || 
	stripos($user_agent, 'diavol') || 
	stripos($user_agent, 'dotbot') || 
	stripos($user_agent, 'finder') || 
	stripos($user_agent, 'flicky') || 
	stripos($user_agent, 'libwww') || 
	stripos($user_agent, 'nutch') || 
	stripos($user_agent, 'planet') || 
	stripos($user_agent, 'purebot') || 
	stripos($user_agent, 'pycurl') || 
	stripos($user_agent, 'skygrid') || 
	stripos($user_agent, 'sucker') || 
	stripos($user_agent, 'turnit') || 
	stripos($user_agent, 'vikspi') || 
	stripos($user_agent, 'zmeu')
) {
	@header('HTTP/1.1 403 Forbidden');
	@header('Status: 403 Forbidden');
	@header('Connection: Close');
	@exit;
} 

Note: If this is your first time adding code snippets in WordPress, then please refer to our guide on how to properly copy / paste code snippets in WordPress, so you don’t accidentally break your site.

If you liked this code snippet, please consider checking out our other articles on the site like: 18 best WordPress comments plugins and how to create a popup form in WordPress.