ET MALWARE Observed Certificate Containing Possible Base64 Encoded Powershell Inbound

Query · suricata

flow:established,to_client;
http.stat_code;
content:"200";
file.data;
content:"-----BEGIN CERTIFICATE-----|0d 0a|JE"; depth:100; fast_pattern;
isdataat:300,relative;
Raw source ET MALWARE Observed Certificate Containing Possible Base64 Encoded Powershell Inbound · Suricata
Esc
Published by Emerging Threats Open ↗, licensed under BSD 3-Clause ↗. Line breaks added for readability; the rule is otherwise unchanged. 
alert http $EXTERNAL_NET any -> $HOME_NET any (
    msg:"ET MALWARE Observed Certificate Containing Possible Base64 Encoded Powershell Inbound";
    flow:established,to_client;
    http.stat_code;
    content:"200";
    file.data;
    content:"-----BEGIN CERTIFICATE-----|0d 0a|JE"; depth:100; fast_pattern;
    isdataat:300,relative;
    classtype:trojan-activity;
    sid:2029278; rev:1;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_01_14, deployment Perimeter, confidence Medium, signature_severity Major, updated_at 2020_01_14;
)

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.