alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Possible Upatre Downloader SSL certificate (fake org)"; flow:established,to_client; tls.cert_subject; content:!"OU=cnc"; content:"OU="; pcre:"/^(?P<fake_org>([asdfgh]+|[qwerty]+|[zxcvbn]+|[23werf]+)).+?OU\x3d(?P=fake_org)/R"; classtype:trojan-activity; sid:2018005; rev:8; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2014_01_22, deployment Perimeter, malware_family Upatre, performance_impact Significant, confidence Medium, signature_severity Critical, tag SSL_Malicious_Cert, tag Exploit_Kit, tag Downloader, tag Upatre, updated_at 2024_04_23;)