ET PHISHING Observed Let's Encrypt Certificate containing Instagram

Query · suricata

flow:established,to_client;
tls.cert_subject;
content:"instagram"; nocase; fast_pattern;
tls.cert_issuer;
content:"Let's Encrypt";
Raw source ET PHISHING Observed Let's Encrypt Certificate containing Instagram · 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 PHISHING Observed Let's Encrypt Certificate containing Instagram";
    flow:established,to_client;
    tls.cert_subject;
    content:"instagram"; nocase; fast_pattern;
    tls.cert_issuer;
    content:"Let's Encrypt";
    classtype:social-engineering;
    sid:2030619; rev:2;
    metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2020_07_30, deployment Perimeter, confidence Medium, signature_severity Major, tag Phishing, updated_at 2020_07_30;
)

Detection rules belong to the projects that publish them and remain under their own licenses. This site indexes and links to them; it claims no rights in them.