alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET EXPLOIT_KIT ZPHP Domain in TLS SNI (viertofly .com)"; flow:established,to_server; tls.sni; bsize:13; content:"viertofly.com"; fast_pattern; reference:url,www.proofpoint.com/us/blog/threat-insight/are-you-sure-your-browser-date-current-landscape-fake-browser-updates; classtype:exploit-kit; sid:2067633; rev:1; metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2026_02_11, deployment Perimeter, performance_impact Low, signature_severity Minor, tag Exploit_Kit, tag compromised_website, updated_at 2026_02_11, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1189, mitre_technique_name Drive_by_Compromise;)