How We Cut 92% of SIEM Noise by Filtering Packets at the Linux Kernel Boundary

Eliminating Alert Fatigue at the Linux Kernel Boundary

Enterprise Security Operations Centers (SOCs) are drowning in alerts. A standard enterprise cluster running thousands of microservices generates tens of millions of raw audit events per day. Traditional userspace monitoring daemons parse gigabytes of syslog streams, creating severe CPU overhead and massive noise.

The fundamental flaw in traditional endpoint detection is where the telemetry is captured. Userspace logging captures events after context is lost, forcing SIEM engines to rely on brittle post-hoc heuristic correlations.

The solution to SIEM noise is not more complex cloud correlation rules; it is intelligent socket-level filtering at ring-0 before false positives are ever emitted.

The Power of Socket-Level eBPF Probes

Extended Berkeley Packet Filter (eBPF) allows verified, sandboxed byte-code to execute directly within the Linux kernel in response to system call events, tracepoints, and network socket operations.

By attaching eBPF kprobes to socket connection primitives (`sys_enter_connect` and `inet_csk_accept`), security operators can evaluate process ancestry, container namespaces, and network destination tuples simultaneously in microseconds:

SEC("kprobe/sys_enter_connect")
int trace_connect(struct pt_regs *ctx) {
    u32 pid = bpf_get_current_pid_tgid() >> 32;
    struct task_struct *task = (struct task_struct *)bpf_get_current_task();

    // Discard verified container health checks inside kernel space
    if (is_whitelisted_health_probe(task)) {
        return 0; // Never reaches userspace syslog
    }

    bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, &telemetry, sizeof(telemetry));
    return 0;
}

By embedding intelligence directly at the system call boundary, security teams transform log flooding into high-fidelity signal.