Kernel-Level Security with Tetragon¶

Tetragon provides eBPF-based security observability at the Linux kernel level. While the OpenClaw plugin captures application-level telemetry, Tetragon sees what actually happens at the system call level — file access, process execution, network connections, and privilege changes.

This is defense in depth: the application layer shows what the agent intended to do; the kernel layer shows what it actually did.

Why Tetragon for OpenClaw?¶

AI agents can execute commands, read files, and make network connections. Even with application-level monitoring, a compromised or manipulated agent could:

Access sensitive files (.env, SSH keys, credentials)
Execute dangerous commands (rm -rf, curl | sh)
Attempt privilege escalation
Make unexpected network connections

Tetragon catches all of this at the kernel level — tamper-proof and impossible to bypass.

Installation¶

Prerequisites¶

Linux kernel 5.4+ (BTF support required)
Root access for installation
systemd (for service management)

Install Tetragon¶

# Download latest release
curl -LO https://github.com/cilium/tetragon/releases/latest/download/tetragon-v1.6.0-amd64.tar.gz

# Extract
tar -xzf tetragon-v1.6.0-amd64.tar.gz
cd tetragon-v1.6.0-amd64

# Install
sudo ./install.sh

# Verify installation
tetra version

Create OpenClaw Policy Directory¶

sudo mkdir -p /etc/tetragon/tetragon.tp.d/openclaw

TracingPolicies for OpenClaw¶

Create the following policy files in /etc/tetragon/tetragon.tp.d/openclaw/:

1. Process Execution Monitoring¶

Captures every command executed by Node.js (OpenClaw).

# /etc/tetragon/tetragon.tp.d/openclaw/01-process-exec.yaml
apiVersion: cilium.io/v1alpha1
kind: TracingPolicy
metadata:
  name: openclaw-process-exec
spec:
  kprobes:
    - call: "sys_execve"
      syscall: true
      args:
        - index: 0
          type: "string"
        - index: 1
          type: "string"
      selectors:
        - matchBinaries:
            - operator: "In"
              values:
                - "/usr/bin/node"
                - "/usr/local/bin/node"
          matchActions:
            - action: Post

2. Sensitive File Access Detection¶

Alerts when OpenClaw accesses sensitive files.

# /etc/tetragon/tetragon.tp.d/openclaw/02-sensitive-files.yaml
apiVersion: cilium.io/v1alpha1
kind: TracingPolicy
metadata:
  name: openclaw-sensitive-files
spec:
  kprobes:
    - call: "security_file_open"
      syscall: false
      args:
        - index: 0
          type: "file"
      selectors:
        - matchBinaries:
            - operator: "In"
              values:
                - "/usr/bin/node"
                - "/usr/local/bin/node"
          matchArgs:
            - index: 0
              operator: "Prefix"
              values:
                - "/etc/shadow"
                - "/etc/passwd"
                - "/etc/sudoers"
                - "/root/"
                - ".ssh/"
                - ".aws/"
                - ".kube/"
                - ".config/gcloud/"
                - ".openclaw/"
                - ".env"
          matchActions:
            - action: Post

3. Privilege Escalation Detection¶

Catches attempts to change user/group ID.

# /etc/tetragon/tetragon.tp.d/openclaw/04-privilege-escalation.yaml
apiVersion: cilium.io/v1alpha1
kind: TracingPolicy
metadata:
  name: openclaw-privilege-escalation
spec:
  kprobes:
    - call: "sys_setuid"
      syscall: true
      args:
        - index: 0
          type: "int"
      selectors:
        - matchBinaries:
            - operator: "In"
              values:
                - "/usr/bin/node"
                - "/usr/local/bin/node"
          matchActions:
            - action: Post
    - call: "sys_setgid"
      syscall: true
      args:
        - index: 0
          type: "int"
      selectors:
        - matchBinaries:
            - operator: "In"
              values:
                - "/usr/bin/node"
                - "/usr/local/bin/node"
          matchActions:
            - action: Post

4. Dangerous Command Detection¶

Flags potentially dangerous binaries.

# /etc/tetragon/tetragon.tp.d/openclaw/05-dangerous-commands.yaml
apiVersion: cilium.io/v1alpha1
kind: TracingPolicy
metadata:
  name: openclaw-dangerous-commands
spec:
  kprobes:
    - call: "sys_execve"
      syscall: true
      args:
        - index: 0
          type: "string"
        - index: 1
          type: "string"
      selectors:
        - matchArgs:
            - index: 0
              operator: "Postfix"
              values:
                - "/rm"
                - "/dd"
                - "/nc"
                - "/netcat"
                - "/ncat"
                - "/curl"
                - "/wget"
                - "/chmod"
                - "/chown"
          matchActions:
            - action: Post

5. Kernel Module Loading¶

Detects attempts to load kernel modules (critical security event).

# /etc/tetragon/tetragon.tp.d/openclaw/06-kernel-modules.yaml
apiVersion: cilium.io/v1alpha1
kind: TracingPolicy
metadata:
  name: openclaw-kernel-modules
spec:
  kprobes:
    - call: "__x64_sys_init_module"
      syscall: true
      args:
        - index: 2
          type: "string"
      selectors:
        - matchActions:
            - action: Post
    - call: "__x64_sys_finit_module"
      syscall: true
      args:
        - index: 2
          type: "string"
      selectors:
        - matchActions:
            - action: Post

Configure Tetragon Export¶

Configure Tetragon to export events to a log file that the OTel Collector can read:

# Set export file
echo "/var/log/tetragon/tetragon.log" | sudo tee /etc/tetragon/tetragon.conf.d/export-filename

# Set file permissions (readable by collector)
echo "644" | sudo tee /etc/tetragon/tetragon.conf.d/export-file-perm

# Rotate at 50MB
echo "50" | sudo tee /etc/tetragon/tetragon.conf.d/export-file-max-size-mb

# Keep 3 backup files
echo "3" | sudo tee /etc/tetragon/tetragon.conf.d/export-file-max-backups

Start Tetragon¶

# Enable and start
sudo systemctl enable tetragon
sudo systemctl start tetragon

# Verify policies loaded
sudo systemctl status tetragon

# Watch events in real-time
sudo tetra getevents -o compact

OTel Collector Integration¶

Add the Tetragon filelog receiver to your collector configuration:

receivers:
  # ... existing receivers ...

  filelog/tetragon:
    include:
      - /var/log/tetragon/tetragon.log
    start_at: end
    operators:
      - type: json_parser
        parse_from: body
        timestamp:
          parse_from: attributes.time
          layout: '%Y-%m-%dT%H:%M:%S.%LZ'

processors:
  # ... existing processors ...

  # Transform Tetragon events
  transform/tetragon:
    error_mode: ignore
    log_statements:
      - context: log
        statements:
          # Identify event type
          - set(attributes["tetragon.type"], "kprobe") where attributes["process_kprobe"] != nil
          - set(attributes["tetragon.type"], "exec") where attributes["process_exec"] != nil
          - set(attributes["tetragon.type"], "exit") where attributes["process_exit"] != nil

          # Extract policy name
          - set(attributes["tetragon.policy"], attributes["process_kprobe"]["policy_name"]) where attributes["process_kprobe"]["policy_name"] != nil

          # Extract process info
          - set(attributes["process.binary"], attributes["process_kprobe"]["process"]["binary"]) where attributes["process_kprobe"]["process"]["binary"] != nil
          - set(attributes["process.pid"], attributes["process_kprobe"]["process"]["pid"]) where attributes["process_kprobe"]["process"]["pid"] != nil

          # Extract function name
          - set(attributes["tetragon.function"], attributes["process_kprobe"]["function_name"]) where attributes["process_kprobe"]["function_name"] != nil

          # Assign security risk levels
          - set(attributes["security.risk"], "critical") where attributes["tetragon.policy"] == "openclaw-privilege-escalation"
          - set(attributes["security.risk"], "critical") where attributes["tetragon.policy"] == "openclaw-kernel-modules"
          - set(attributes["security.risk"], "high") where attributes["tetragon.policy"] == "openclaw-sensitive-files"
          - set(attributes["security.risk"], "high") where attributes["tetragon.policy"] == "openclaw-dangerous-commands"
          - set(attributes["security.risk"], "low") where attributes["tetragon.policy"] == "openclaw-process-exec"

  # Add service metadata
  resource/tetragon:
    attributes:
      - key: service.name
        value: "openclaw-security"
        action: upsert
      - key: tetragon.version
        value: "1.6.0"
        action: upsert

service:
  pipelines:
    # ... existing pipelines ...

    logs/tetragon:
      receivers: [filelog/tetragon]
      processors: [transform/tetragon, resource/tetragon, batch]
      exporters: [otlphttp/dynatrace]  # or your exporter

Collector Permissions¶

The OTel Collector needs read access to the Tetragon log file:

# Make log readable
sudo chmod 644 /var/log/tetragon/tetragon.log

# Or add collector user to appropriate group
sudo usermod -a -G adm otelcol-contrib

Event Examples¶

Process Execution Event¶

{
  "process_kprobe": {
    "process": {
      "binary": "/usr/bin/node",
      "pid": 58856,
      "uid": 1000,
      "cwd": "/home/user"
    },
    "parent": {
      "binary": "/usr/bin/node",
      "pid": 56271
    },
    "function_name": "__x64_sys_execve",
    "args": [
      {"string_arg": "/bin/sh"},
      {"string_arg": "-c ls -la"}
    ],
    "policy_name": "openclaw-process-exec"
  },
  "time": "2026-02-04T15:13:03.638Z"
}

Sensitive File Access Event¶

{
  "process_kprobe": {
    "process": {
      "binary": "/usr/bin/node",
      "pid": 58900
    },
    "function_name": "security_file_open",
    "args": [
      {"file_arg": {"path": "/home/user/.ssh/id_rsa"}}
    ],
    "policy_name": "openclaw-sensitive-files"
  },
  "time": "2026-02-04T15:14:22.123Z"
}

Alerting on Security Events¶

In your observability backend (Dynatrace, Grafana, etc.), create alerts for:

Alert	Condition	Severity
Privilege Escalation	`tetragon.policy == "openclaw-privilege-escalation"`	Critical
Kernel Module Load	`tetragon.policy == "openclaw-kernel-modules"`	Critical
Sensitive File Access	`tetragon.policy == "openclaw-sensitive-files"`	High
Dangerous Command	`tetragon.policy == "openclaw-dangerous-commands"`	High
Unusual Process Exec	`tetragon.policy == "openclaw-process-exec"` AND off-hours	Medium

Complete Observability Stack¶

With Tetragon integrated, you have three layers of visibility:

Layer	Source	What It Shows
Application	OpenClaw Plugin	Tool calls, tokens, request flow
Gateway	diagnostics-otel	Session health, queues, costs
Kernel	Tetragon	System calls, file access, network

This provides defense in depth — even if application-level telemetry is manipulated, kernel-level events reveal the truth.

Troubleshooting¶

Tetragon not starting¶

# Check logs
sudo journalctl -u tetragon -n 50

# Common issues:
# - Kernel too old (need 5.4+)
# - BTF not available
# - Policy YAML syntax error

Events not appearing in collector¶

# Check Tetragon is writing events
sudo tail -f /var/log/tetragon/tetragon.log

# Check file permissions
ls -la /var/log/tetragon/tetragon.log

# Check collector logs
sudo journalctl -u otelcol-contrib | grep tetragon

High kernel overhead¶

If Tetragon causes performance issues, reduce policy scope:

Use matchBinaries to limit to Node.js only
Remove high-volume policies (like process-exec) if not needed
Increase rate limits in policies