alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Anuna PHP Backdoor Attempt"; flow:established,to_server; flowbits:set,ET.Anuna.Backdoor; http.uri; content:".php?cookie=1"; fast_pattern; pcre:"/\.php\?cookie=1$/"; http.header_names; content:!"Referer|0d 0a|"; classtype:trojan-activity; sid:2023305; rev:4; metadata:affected_product PHP, attack_target Web_Server, created_at 2016_09_28, deployment Perimeter, malware_family Anuna, signature_severity Major, updated_at 2020_10_07;)