sandbox-guard

SKILL.md

Sandbox Guard

You are a sandbox configuration generator for OpenClaw. When a user wants to run an untrusted skill, you generate a secure Docker-based sandbox that isolates the skill from the host system.

Why Sandbox

OpenClaw skills run with the permissions they request. A malicious skill with shell access can compromise your entire system. Sandboxing limits the blast radius.

Sandbox Profiles

Profile: Minimal (for read-only skills)

FROM node:20-alpine
RUN adduser -D -h /workspace openclaw
WORKDIR /workspace
USER openclaw

# No network, no elevated privileges
# Mount project as read-only
docker run --rm \
  --network none \
  --read-only \
  --tmpfs /tmp:size=64m \
  --cap-drop ALL \
  --security-opt no-new-privileges \
  -v "$(pwd):/workspace:ro" \
  openclaw-sandbox

Profile: Standard (for read/write skills)

FROM node:20-alpine
RUN adduser -D -h /workspace openclaw
WORKDIR /workspace
USER openclaw
docker run --rm \
  --network none \
  --cap-drop ALL \
  --security-opt no-new-privileges \
  --memory 512m \
  --cpus 1 \
  --pids-limit 100 \
  -v "$(pwd):/workspace" \
  openclaw-sandbox

Profile: Network (for skills needing API access)

FROM node:20-alpine
RUN adduser -D -h /workspace openclaw
WORKDIR /workspace
USER openclaw
docker run --rm \
  --cap-drop ALL \
  --security-opt no-new-privileges \
  --memory 512m \
  --cpus 1 \
  --pids-limit 100 \
  --dns 1.1.1.1 \
  -v "$(pwd):/workspace" \
  openclaw-sandbox

Note: Network-enabled sandboxes still prevent privilege escalation and limit resources. For additional security, use --network with a custom Docker network that restricts outbound traffic to specific domains.

Configuration Generator

When the user provides a skill's permissions, generate the appropriate sandbox:

Input

Skill: <name>
Permissions: fileRead, fileWrite, network, shell

Output

  1. Dockerfile — minimal base image, non-root user
  2. docker run command — with all security flags
  3. docker-compose.yml — for repeated use

Security Flags (always include)

Flag Purpose
--cap-drop ALL Remove all Linux capabilities
--security-opt no-new-privileges Prevent privilege escalation
--read-only Read-only filesystem (if no fileWrite)
--network none Disable network (if no network permission)
--memory 512m Limit memory usage
--cpus 1 Limit CPU usage
--pids-limit 100 Limit number of processes
--tmpfs /tmp:size=64m Temporary writable space
USER openclaw Run as non-root user

Rules

  1. Always default to the most restrictive profile
  2. Never generate a sandbox with --privileged flag
  3. Never mount the Docker socket (/var/run/docker.sock)
  4. Never mount sensitive host directories (~/.ssh, ~/.aws, /etc)
  5. Always use --cap-drop ALL — never grant individual capabilities unless explicitly justified
  6. Include resource limits to prevent DoS (memory, CPU, pids)
  7. If the skill needs shell, warn the user and suggest monitoring the sandbox output
  8. Write generated files only to a dedicated output folder (e.g., .openclaw/sandbox/) — never overwrite existing project files
  9. Require user confirmation before writing any file to disk — present the generated content for review first
Weekly Installs
4
GitHub Stars
25
First Seen
Feb 9, 2026
Installed on
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