ET MALWARE Win32/Tofsee Connectivity Check M3

Query · suricata

flow:to_server,established;
urilen:1;
http.method;
content:"GET";
http.user_agent;
content:"Mozilla/5.0 |28|Windows NT 10.0|3b 20|Win64|3b 20|x64|29| AppleWebKit/537.36 |28|KHTML, like Gecko|29| Chrome/90.0.4430.85 Safari/537.36 OPR/76.0.4017.94"; bsize:131;
http.host;
content:"checkip.dyndns.org"; endswith; fast_pattern;
http.header_names;
content:!"Referer|0d 0a|";
Raw source ET MALWARE Win32/Tofsee Connectivity Check M3 · 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 Win32/Tofsee Connectivity Check M3";
    flow:to_server,established;
    urilen:1;
    http.method;
    content:"GET";
    http.user_agent;
    content:"Mozilla/5.0 |28|Windows NT 10.0|3b 20|Win64|3b 20|x64|29| AppleWebKit/537.36 |28|KHTML, like Gecko|29| Chrome/90.0.4430.85 Safari/537.36 OPR/76.0.4017.94"; bsize:131;
    http.host;
    content:"checkip.dyndns.org"; endswith; fast_pattern;
    http.header_names;
    content:!"Referer|0d 0a|";
    reference:md5,cc171ee77dc2d657e0c018fcad17608f;
    classtype:trojan-activity;
    sid:2033325; rev:1;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_07_15, deployment Perimeter, malware_family Win32_Tofsee, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_07_15;
)

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