alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE WEBC2-DIV UA"; flow:established,to_server; http.user_agent; content:"Microsoft Internet Explorer Exelon|20|"; depth:35; fast_pattern; reference:url,www.mandiant.com/apt1; reference:md5,1e5ec6c06e4f6bb958dcbb9fc636009d; classtype:command-and-control; sid:2016454; rev:4; metadata:created_at 2013_02_22, signature_severity Major, updated_at 2020_10_14;)