alert http any any -> $HOME_NET any (msg:"ET EXPLOIT Possible Zyxel Authentication Bypass Inbound (CVE-2021-3297)"; http.method; content:"GET"; http.uri; content:"/login_ok.htm"; fast_pattern; http.cookie; content:"login=1"; reference:url,github.com/Sec504/Zyxel-NBG2105-CVE-2021-3297; reference:cve,2021-3297; classtype:attempted-user; sid:2032523; rev:2; metadata:created_at 2021_04_06, cve CVE_2021_3297, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_04_28, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application; target:dest_ip;)