alert http any any -> any any (msg:"TOOLS [PTsecurity] Sliver C2 HTTP Key exchange (gzip)"; flow:established, to_server; http.method; content:"POST"; http.uri; pcre:"/\?(?:[a-z_]=[a-z0-9_]{7,14}&[a-z_]{2}=[a-z0-9_]{8,13}|[a-z_]{2}=[a-z0-9_]{8,13}&[a-z_]=[a-z0-9_]{7,14}|[a-z_]=[a-z0-9_]{7,14})$/U"; http.header.raw; content:!"Cookie|3a|"; nocase; content:"|0d 0a|Accept-Encoding|3A| gzip|0d 0a|"; nocase; http.content_len; byte_test:0, >=, 133, 0, string, dec; byte_test:0, <=, 295, 0, string, dec; pkt_data; content:"|0D 0A 0D 0A 1F 8B 08 00 00 00 00|"; reference:url, virustotal.com/gui/file/e877e29e45b823fe32c600508dd9e05e399272c98449976b66f44721e54e42e3/detection; reference:url, github.com/BishopFox/sliver; reference:url, rules.ptsecurity.com; classtype:attempted-admin; sid:10008539; rev:6;)