alert udp $EXTERNAL_NET any -> $HOME_NET 1900 (msg:"GPL MISC UPnP service discover attempt"; content:"M-SEARCH "; depth:9; content:"ssdp|3A|discover"; classtype:network-scan; sid:2101917; rev:7; metadata:created_at 2010_09_23, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)