alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Observed Cloudflare Universal (Shared) Certificate, Retired"; flow:established,to_server; tls.sni; content:"sni."; depth:4; pcre:"/(?:/d{6})/R"; content:".cloudflaressl.com"; fast_pattern; offset:9; reference:url,community.cloudflare.com/t/cloudflare-universal-and-universal-shared-certificates/59523; classtype:misc-activity; sid:2035203; rev:2; metadata:created_at 2022_02_15, deployment Perimeter, deployment SSLDecrypt, performance_impact Low, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_02_15;)