alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (msg:"ET WEB_SPECIFIC_APPS Piwik Backdoor Access"; flow:established,to_server; http.uri; content:"/core/Loader.php?"; fast_pattern; nocase; content:"g="; content:"s="; reference:url,blog.sucuri.net/2012/11/piwik-org-webserver-hacked-and-backdoor-added-to-piwik.html; classtype:web-application-attack; sid:2015947; rev:5; metadata:created_at 2012_11_28, signature_severity Major, updated_at 2020_09_17;)