ET USER_AGENTS Observed Suspicious UA (\xa4)

Query · suricata

flow:established,to_server;
http.header;
content:"|0d 0a|User-Agent|3a 20 a4 0d 0a|"; fast_pattern;
http.user_agent;
content:"|a4|"; bsize:1;
Raw source ET USER_AGENTS Observed Suspicious UA (\xa4) · 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 USER_AGENTS Observed Suspicious UA (\xa4)";
    flow:established,to_server;
    http.header;
    content:"|0d 0a|User-Agent|3a 20 a4 0d 0a|"; fast_pattern;
    http.user_agent;
    content:"|a4|"; bsize:1;
    classtype:bad-unknown;
    sid:2029554; rev:2;
    metadata:affected_product Any, attack_target Client_Endpoint, created_at 2020_03_02, deployment Perimeter, confidence High, signature_severity Minor, updated_at 2024_03_08;
)

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