alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE RedControle Communicating with CnC"; flow:established,to_server; content:"SE_ND_CO_NN_EC|23|"; depth:15; fast_pattern; content:"|23|"; within:20; content:"|23|"; endswith; reference:url,threatvector.cylance.com/en_us/home/poking-the-bear-three-year-campaign-targets-russian-critical-infrastructure.html; reference:md5,855b937f668ecd90b8be004fd3c24717; classtype:command-and-control; sid:2026724; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2018_12_13, deployment Perimeter, malware_family RedControle, performance_impact Low, confidence High, signature_severity Major, updated_at 2022_03_24;)