✄𐘗
text code block:
✄𐘗from logs-endpoint.events.process-* metadata _id, _index, _version
| mv_expand event.action 
| where
    host.os.type == "linux" and
    event.type == "start" and
    event.action == "exec" and (
        (
            process.name in ("base64", "base64plain", "base64url", "base64mime", "base64pem", "base32", "base16") and
            process.command_line like "*-*d*"
        ) or
        (
            process.name == "openssl" and
            process.args == "enc" and
            process.args in ("-d", "-base64", "-a")
        ) or
        (
            process.name like "python*" and (
                (
                    process.args == "base64" and
                    process.args in ("-d", "-u", "-t")
                ) or
                (
                    process.args == "-c" and
                    process.command_line like "*base64*" and
                    process.command_line like "*b64decode*"
                )
            )
        ) or
        (
            process.name like "perl*" and
            process.command_line like "*decode_base64*"
        ) or
        (
            process.name like "ruby*" and
            process.args == "-e" and
            process.command_line like "*Base64.decode64*"
        )
    )
| keep
    @timestamp,
    _id,
    _index,
    _version,
    host.os.type,
    event.type,
    event.action,
    process.name,
    process.args,
    process.command_line,
    process.parent.name,
    process.parent.command_line,
    agent.id,
    host.name,
    event.dataset,
    data_stream.namespace
| stats
    Esql.event_count = count(),
    Esql.process_parent_name_values = values(process.parent.name),
    Esql.process_parent_command_line_values = values(process.parent.command_line),
    Esql.agent_id_count_distinct = count_distinct(agent.id),
    Esql.host_name_values = values(host.name),
    Esql.agent_id_values = values(agent.id),
    Esql.event_dataset_values = values(event.dataset),
    Esql.data_stream_namespace_values = values(data_stream.namespace)
    by process.name, process.command_line
| where
    Esql.agent_id_count_distinct == 1 and
    Esql.event_count < 15
| sort Esql.event_count asc

// Extract unique values to ECS fields for alerts exclusion
| eval agent.id = mv_min(Esql.agent_id_values),
       host.name = mv_min(Esql.host_name_values)

| keep agent.id, host.name, process.name, process.command_line, Esql.*