ET MALWARE Cobalt Strike Activity (GET)

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Cobalt Strike Activity (GET)";
    flow:to_server,established;
    http.method;
    content:"GET";
    http.uri;
    content:"/r-arrow"; startswith; fast_pattern;
    http.user_agent;
    content:"Mozilla|2f|5|2e|0|20 28|Windows|20|NT|20|10|2e|0|3b 20|Win64|3b 20|x64|29 20|AppleWebKit|2f|537|2e|36|20 28|KHTML|2c 20|like|20|Gecko|29 20|Chrome|2f|42|2e|0|2e|2311|2e|135|20|Safari|2f|537|2e|36|20|Edge|2f|12|2e|246"; bsize:127;
    http.header_names;
    content:!"Referer";
    reference:md5,2157d05171e0a32c30a8c8350d25335a;
    classtype:trojan-activity;
    sid:2043416; rev:1;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_01_19, deployment Perimeter, deployment SSLDecrypt, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_01_19;
)