Rule History

alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed OtterCookie Domain (alchemy-api-v3 .cloud in TLS SNI)"; flow:established,to_server; tls.sni; dotprefix; content:".alchemy-api-v3.cloud"; endswith; fast_pattern; reference:url,jp.security.ntt/tech_blog/en-contagious-interview-ottercookie; classtype:trojan-activity; sid:2060628; rev:2; metadata:attack_target Client_Endpoint, created_at 2025_03_05, deployment Perimeter, deprecation_reason Age, malware_family OtterCookie, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2025_04_15, reviewed_at 2025_04_15;)