alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Observed Proxy Domain (proxynet .io in TLS SNI)"; flow:established,to_server; tls.sni; content:"proxynet.io"; bsize:11; fast_pattern; classtype:misc-activity; sid:2035758; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_04_05, deployment Perimeter, deprecation_reason Relevance, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_05_10;)