alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE ShadowLink IoT Botnet CnC Tasking Output Response"; flow:established,to_server; http.method; content:"POST"; http.uri; bsize:4; content:"/b/r"; http.header; content:"X-B|3a 20|"; fast_pattern; http.request_body; content:"|22|b|22|"; content:"|22|r|22|"; reference:url,ctrlaltintel.com/research/ProxyPCP/; classtype:trojan-activity; sid:2068793; rev:1; metadata:affected_product IoT, attack_target Networking_Equipment, tls_state TLSDecrypt, created_at 2026_04_15, deployment Perimeter, deployment SSLDecrypt, malware_family ShadowLink, performance_impact Low, confidence High, signature_severity Major, updated_at 2026_04_15; target:src_ip;)