alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET USER_AGENTS Observed Donot Group UA (Mozilla FireFox)"; flow:established,to_server; http.user_agent; bsize:21; content:"Mozilla FireFox 61.00"; reference:md5,8f2829a963c3b6f247ac77e0bf992bf1; classtype:trojan-activity; sid:2044207; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_02_15, deployment Perimeter, deployment SSLDecrypt, malware_family DonotGroup, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_03_26;)