alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO DYNAMIC_DNS HTTP Request to a *.servehttp .com Domain"; flow:established,to_server; http.host; content:".servehttp.com"; fast_pattern; endswith; reference:url,www.noip.com/support/faq/free-dynamic-dns-domains/; reference:url,blogs.cisco.com/security/dynamic-detection-of-malicious-ddns/; reference:url,labs.umbrella.com/2013/04/15/on-the-trail-of-malicious-dynamic-dns-domains/; classtype:bad-unknown; sid:2018212; rev:6; metadata:attack_target Client_and_Server, created_at 2014_03_05, deployment Perimeter, performance_impact Low, confidence High, signature_severity Informational, updated_at 2023_08_08, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1568, mitre_technique_name Dynamic_Resolution;)