alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET JA3 Hash - Possible RustyBuer Server Response"; flowbits:isset,ET.rustybuer; ja3s.hash; content:"f6dfdd25d1522e4e1c7cd09bd37ce619"; reference:md5,ea98a9d6ca6f5b2a0820303a1d327593; classtype:bad-unknown; sid:2032960; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_05_13, deployment Perimeter, malware_family RustyBuer, performance_impact Low, confidence Low, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_05_13;)