alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET EXPLOIT MVPower DVR Shell UCE MSF Check"; flow:to_server,established; http.uri; content:"/shell?echo+"; depth:12; fast_pattern; http.header_names; content:!"Referer"; reference:url,researchcenter.paloaltonetworks.com/2018/07/unit42-finds-new-mirai-gafgyt-iotlinux-botnet-campaigns/; classtype:attempted-admin; sid:2025882; rev:3; metadata:affected_product Linux, attack_target IoT, created_at 2018_07_23, deployment Perimeter, malware_family Mirai, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_08_25;)