alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32.Sality.3 Checkin"; flow:established,to_server; http.uri; content:"/?f"; fast_pattern; endswith; http.header; content:!"broadcastify.com"; http.header_names; content:!"User-Agent|0d 0a|"; content:!"Accept"; content:!"Referer|0d 0a|"; content:!"Cache-Control|0d 0a|"; reference:md5,df9516919e75853742e63db318e7d346; classtype:command-and-control; sid:2020505; rev:6; metadata:created_at 2015_02_24, deprecation_reason Relevance, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_12_22;)