alert udp $EXTERNAL_NET any -> $HOME_NET 5060 (msg:"ET SCAN Sipvicious Scan"; content:"From|3A 20 22|sipvicious"; threshold:type limit, count 1, seconds 10, track by_src; reference:url,blog.sipvicious.org; classtype:attempted-recon; sid:2008578; rev:4; metadata:created_at 2010_07_30, confidence Medium, signature_severity Informational, updated_at 2019_07_26;)