ET MALWARE User-Agent in Referer Field - Likely Malware

Query · suricata

flow:established,to_server;
http.referer;
content:"Mozilla/4.0|20|"; startswith;
Raw source ET MALWARE User-Agent in Referer Field - Likely Malware · Suricata
Esc
Published by Emerging Threats Open ↗, licensed under BSD 3-Clause ↗. Line breaks added for readability; the rule is otherwise unchanged. 
alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE User-Agent in Referer Field - Likely Malware";
    flow:established,to_server;
    http.referer;
    content:"Mozilla/4.0|20|"; startswith;
    classtype:trojan-activity;
    sid:2013423; rev:10;
    metadata:created_at 2011_08_18, confidence Medium, signature_severity Major, updated_at 2020_12_22;
)

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