alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Clipsa Stealer - CnC Checkin"; flow:established,to_server; threshold:type limit, track by_src, count 1, seconds 30; http.method; content:"POST"; http.uri; content:"/wp-content/plugins/WPSecurity/load.php"; depth:39; fast_pattern; endswith; http.request_body; pcre:"/^[a-zA-Z0-9]+$/"; http.content_type; content:"application/x-www-form-urlencoded"; http.content_len; byte_test:0,<=,400,0,string,dec; http.header_names; content:!"Referer"; reference:md5,7e52633ffa2c3aee03e8b26f03e07cc4; reference:url,decoded.avast.io/janrubin/clipsa-multipurpose-password-stealer/; classtype:command-and-control; sid:2027893; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_08_16, deployment Perimeter, malware_family Clipsa, performance_impact Low, confidence High, signature_severity Major, tag Stealer, updated_at 2020_09_17;)