alert tcp any any -> $HOME_NET any (
msg:"ET EXPLOIT TLS HeartBeat Request (Server Initiated) fb set";
flow:established,from_server;
content:"|18 03|"; depth:2;
byte_test:1,<,4,2;
flowbits:isnotset,ET.HB.Response.SI;
flowbits:set,ET.HB.Request.SI;
flowbits:noalert;
reference:cve,2014-0160;
reference:url,blog.inliniac.net/2014/04/08/detecting-openssl-heartbleed-with-suricata/;
reference:url,heartbleed.com/;
reference:url,blog.fox-it.com/2014/04/08/openssl-heartbleed-bug-live-blog/;
classtype:bad-unknown;
sid:2018375; rev:4;
metadata:created_at 2014_04_09, cve CVE_2014_0160, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_08_16;
)