alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win.Trojan.Chewbacca connectivity check"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/ip/"; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|Synapse)"; fast_pattern; http.header_names; content:!"Accept"; content:!"Referer"; reference:md5,21f8b9d9a6fa3a0cd3a3f0644636bf09; reference:url,www.symantec.com/security_response/earthlink_writeup.jsp?docid=2013-121813-2446-99; classtype:trojan-activity; sid:2019162; rev:5; metadata:created_at 2014_08_18, signature_severity Major, updated_at 2020_05_06;)