alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET POLICY External Timezone Check (earthtools.org)"; flow:established,to_server; http.uri; content:"/timezone/"; depth:10; http.host; content:"www.earthtools.org"; bsize:18; fast_pattern; http.header_names; content:!"Referer|0d 0a|"; classtype:policy-violation; sid:2021120; rev:3; metadata:created_at 2015_05_20, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_05_22;)