alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Possible SSLv2 Negotiation in Progress Server Hello"; flow:established,to_client; flowbits:set,SSlv2.ServerHello; flowbits:noalert; content:"|04 00 01 00 02|"; offset:2; depth:5; byte_test:2,>,15,4,relative; byte_test:2,<,33,4,relative; reference:url,drownattack.com/drown-attack-paper.pdf; classtype:policy-violation; sid:2022583; rev:3; metadata:created_at 2016_03_02, confidence Medium, signature_severity Informational, updated_at 2024_03_14;)