Rule History

alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET INFO Observed Let's Encrypt Certificate from Backup Intermediate, E2"; flow:from_server,established; tls.cert_issuer; content:"E2"; fast_pattern; reference:url,letsencrypt.org/certificates/; classtype:misc-activity; sid:2035193; rev:2; metadata:created_at 2022_02_14, deployment Perimeter, deployment SSLDecrypt, deprecation_reason Performance, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_02_14;)