alert tcp-pkt $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ValleyRAT CnC Checkin Server Response"; flow:established,to_client; dsize:19; content:"|13 00 00 00 31 00 32 00 33 00 34 00 35 00 36 00 00 00 00|"; fast_pattern; reference:md5,f4d9b144234ff75d669b1265f708ec55; classtype:trojan-activity; sid:2038859; rev:1; metadata:attack_target Client_and_Server, created_at 2022_09_15, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_09_15;)