alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (msg:"ET EXPLOIT Apache log4j RCE Attempt (http rmi) (CVE-2021-44228)"; flow:established,to_server; content:"|24 7b|jndi|3a|rmi|3a 2f 2f|"; nocase; fast_pattern; reference:url,lunasec.io/docs/blog/log4j-zero-day/; reference:cve,2021-44228; classtype:attempted-admin; sid:2034648; rev:1; metadata:attack_target Server, created_at 2021_12_10, cve CVE_2021_44228, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, tag Exploit, tag CISA_KEV, updated_at 2021_12_10, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;)