This is something I came across on perishablepress.com was a way to help protect your website though the .htaccess file.
# 5G BLACKLIST/FIREWALL (2013) # @ https://perishablepress.com/5g-blacklist-2013/ # 5G:[QUERY STRINGS] RewriteEngine On RewriteBase / RewriteCond %{QUERY_STRING} ("|%22).*(<|>|%3) [NC,OR] RewriteCond %{QUERY_STRING} (javascript:).*(;) [NC,OR] RewriteCond %{QUERY_STRING} (<|%3C).*script.*(>|%3) [NC,OR] RewriteCond %{QUERY_STRING} (\|../|`|='$|=%27$) [NC,OR] RewriteCond %{QUERY_STRING} (;|'|"|%22).*(union|select|insert|drop|update|md5|benchmark|or|and|if) [NC,OR] RewriteCond %{QUERY_STRING} (base64_encode|localhost|mosconfig) [NC,OR] RewriteCond %{QUERY_STRING} (boot.ini|echo.*kae|etc/passwd) [NC,OR] RewriteCond %{QUERY_STRING} (GLOBALS|REQUEST)(=|[|%) [NC] RewriteRule .* - [F] # 5G:[USER AGENTS] # SetEnvIfNoCase User-Agent ^$ keep_out SetEnvIfNoCase User-Agent (binlar|casper|cmsworldmap|comodo|diavol|dotbot|feedfinder|flicky|ia_archiver|kmccrew|nutch|planetwork|purebot|pycurl|skygrid|sucker|turnit|vikspider|zmeu) keep_out Order Allow,Deny Allow from all Deny from env=keep_out # 5G:[REQUEST STRINGS] RedirectMatch 403 (https?|ftp|php):// RedirectMatch 403 /(https?|ima|ucp)/ RedirectMatch 403 /(Permanent|Better)$ RedirectMatch 403 (=\'|=\%27|/\'/?|).css()$ RedirectMatch 403 (,|)+|/,/|{0}|(/(|...|+++|||\"\") RedirectMatch 403 .(cgi|asp|aspx|cfg|dll|exe|jsp|mdb|sql|ini|rar)$ RedirectMatch 403 /(contac|fpw|install|pingserver|register).php$ RedirectMatch 403 (base64|crossdomain|localhost|wwwroot|e107_) RedirectMatch 403 (eval(|_vti_|(null)|echo.*kae|config.xml) RedirectMatch 403 .well-known/host-meta RedirectMatch 403 /function.array-rand RedirectMatch 403 );$(this).html( RedirectMatch 403 proc/self/environ RedirectMatch 403 msnbot.htm)._ RedirectMatch 403 /ref.outcontrol RedirectMatch 403 com_cropimage RedirectMatch 403 indonesia.htm RedirectMatch 403 {$itemURL} RedirectMatch 403 function() RedirectMatch 403 labels.rdf RedirectMatch 403 /playing.php RedirectMatch 403 muieblackcat # 5G:[REQUEST METHOD] RewriteCond %{REQUEST_METHOD} ^(TRACE|TRACK) RewriteRule .* - [F] # 5G:[BAD IPS] Order Allow,Deny Allow from all # uncomment/edit/repeat next line to block IPs # Deny from 123.456.789