alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Saturn Proxy Checkin Response"; flow:established,from_server; flowbits:isset,ET.saturn.checkin; content:"200"; http_stat_code; content:"OK"; http_stat_msg; content:"Encryption|3a| on|0d 0a|"; depth:16; classtype:command-and-control; sid:2007752; rev:5; metadata:created_at 2010_07_30, signature_severity Major, updated_at 2019_07_26;)