alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET USER_AGENTS Suspicious User-Agent (FULLSTUFF)"; flow:established,to_server; http.user_agent; content:"FULLSTUFF"; nocase; startswith; reference:url,threatexpert.com/reports.aspx?find=mrb.mail.ru; classtype:trojan-activity; sid:2013880; rev:5; metadata:affected_product Any, attack_target Client_Endpoint, created_at 2011_11_08, deployment Perimeter, confidence High, signature_severity Major, tag User_Agent, updated_at 2020_08_13;)