alert tls $EXTERNAL_NET any -> $HOME_NET any (
msg:"ET MALWARE Observed Malicious SSL Cert (POWERSTATS Proxy CnC)";
flow:from_server,established;
tls.cert_subject;
content:"CN=andresocana.com"; nocase; endswith;
tls.cert_issuer;
content:"C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3";
reference:url,www.clearskysec.com/muddywater-operations-in-lebanon-and-oman/;
classtype:domain-c2;
sid:2026679; rev:3;
metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_and_Server, created_at 2018_11_29, deployment Perimeter, malware_family POWERSTAT, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_16, mitre_tactic_id TA0042, mitre_tactic_name Resource_Development, mitre_technique_id T1587, mitre_technique_name Develop_Capabilities;
)