alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE [PTsecurity] Bladabindi/njRAT (HAMAD versions)"; flow:established,to_server; dsize:<200; content:"|00|"; depth:4; content:"HAMAD"; fast_pattern; within:10; pcre:"/^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})$/R"; reference:md5,cc18ad38eccdf096f0ac5840f380ef4f; classtype:trojan-activity; sid:2025074; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_11_28, deployment Perimeter, malware_family Bladabindi, malware_family njrat, performance_impact Low, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_08_19;)