ET MALWARE SSL/TLS Certificate Observed (WRAT)

Query · suricata

flow:established,to_client;
tls.cert_subject;
content:"CN=alsalaf.info"; fast_pattern;
tls.cert_issuer;
content:"C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3";
Raw source ET MALWARE SSL/TLS Certificate Observed (WRAT) · Suricata
Esc
Published by Emerging Threats Open ↗, licensed under BSD 3-Clause ↗. Line breaks added for readability; the rule is otherwise unchanged. 
alert tls $EXTERNAL_NET any -> $HOME_NET any (
    msg:"ET MALWARE SSL/TLS Certificate Observed (WRAT)";
    flow:established,to_client;
    tls.cert_subject;
    content:"CN=alsalaf.info"; fast_pattern;
    tls.cert_issuer;
    content:"C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3";
    reference:md5,7831f12dac1d4ef7dcd6e3218b8dad68;
    classtype:trojan-activity;
    sid:2031645; rev:2;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_02_22, deployment Perimeter, confidence High, signature_severity Major, tag WRAT, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_02_22;
)

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