Files
paseo/SECURITY.md
Mohamed Boudra 2c9db5279c Run Paseo from an official Docker image (#1740)
* Add Docker images and agent Docker Mods

Ship official container images that run the Paseo daemon headless. One
Dockerfile parametrized by BASE_IMAGE covers Debian 12/13, Ubuntu 22.04/24.04
and Alpine; it bundles Node 22, the npm-published server + CLI, a vendored
s6-overlay as PID 1, and a small Docker Mods loader.

Agents are chosen at runtime via DOCKER_MODS (pipe-separated mod images). Each
mod is a FROM scratch image carrying only an install hook that runs
`npm install -g <agent-cli>`; the loader pulls the layers from the registry,
extracts them, and runs the hook before the daemon starts, so any requested
agent is on PATH when Paseo probes provider availability.

- docker/base: Dockerfile, install scripts, s6 services, mods loader
- docker/mods/*: claude-code, codex, copilot, opencode, pi
- docker/docker-compose.example.yml + docker/README.md
- .github/workflows/docker.yml: multi-arch (amd64/arm64) buildx matrix,
  publishes to ghcr.io/getpaseo on version tags
- docs/docker.md + CLAUDE.md docs index row

* feat(docker): print pairing QR and link on daemon startup

Add an s6 oneshot service that waits for the daemon to listen, then runs
`paseo daemon pair` so the pairing QR code and link surface in the container
logs. Best-effort: never blocks boot, skips gracefully when relay is disabled.
Opt out with PASEO_PAIRING_QR=0.

* build(docker): add Arch image support

* ci(docker): build Arch without Buildx

* docs(docker): document paseo env contract

* feat(docker): add opt-in sudo mode

* docs(docker): link env references

* fix(docker): create agent config dirs

* fix(docker): default home to /home/paseo

* docs(docker): document agent auth setup

* docs(docker): document relay port setup

* fix(docker): install Node from tarball

* docs: add Docker quick start

* docs(docker): remove legacy home example

* docs(docker): set container hostname

* fix(docker): prepare opencode storage

* fix(docker): allow paseo login shell

* fix docker opencode permissions

* ci(docker): use Node 24 actions

* fix(docker): install bzip2 runtime tools

* fix(docker): update Pi mod package

* fix(docker): quiet default daemon logs

* fix(docker): split home from state

Docker images now keep HOME at /home/paseo and store Paseo daemon state under /home/paseo/.paseo by default.

Existing volumes can keep the old layout by setting PASEO_HOME=/home/paseo.

* fix(docker): keep mods out of paseo home

* ci(docker): skip alpine arm64 builds

* fix(docker): address review findings

* fix(docker): verify s6 overlay downloads

* fix(docker): honor custom healthcheck port

* fix(docker): fail on mod extraction errors

* feat(docker): add official container image

Ship a focused daemon image with the bundled web UI enabled and document extending it with agent CLIs.

* ci(docker): publish images only on stable releases

* fix(docker): check daemon health over HTTP

---------

Co-authored-by: Herbrant <cdavide98carnemolla@gmail.com>
2026-06-26 14:48:13 +08:00

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Markdown

# Security
Paseo follows a client-server architecture, similar to Docker. The daemon runs on your machine and manages your coding agents. Clients (the mobile app, CLI, or web interface) connect to the daemon to monitor and control those agents.
Your code never leaves your machine. Paseo is a local-first tool that connects directly to your development environment.
## Architecture
The Paseo daemon can run anywhere you want to execute agents: your laptop, a Mac Mini, a VPS, or a Docker container. The daemon listens for connections and manages agent lifecycles.
Clients connect to the daemon over WebSocket. There are two ways to establish this connection:
- **Relay connection** — The daemon connects outbound to our relay server, and clients meet it there. No open ports required.
- **Direct connection** — The daemon listens on a network address and clients connect directly.
## Relay threat model
The relay is designed to be untrusted. All traffic between your phone and daemon is end-to-end encrypted. The relay server cannot read your messages, see your code, or modify traffic without detection. Even if the relay is compromised, your data remains protected.
### How it works
1. The daemon generates a persistent Curve25519 keypair on first run and stores it at `$PASEO_HOME/daemon-keypair.json` with mode `0600`
2. The pairing URL (rendered as a QR code or opened directly) carries the daemon's public key in its URL fragment (`https://app.paseo.sh/#offer=...`). Fragments are not sent to the web server, so `app.paseo.sh` never sees the key.
3. When the phone connects via the relay, it generates a fresh ephemeral Curve25519 keypair and sends an `e2ee_hello` message containing its public key. The daemon will not process any application messages until this handshake completes.
4. Both sides perform a Curve25519 ECDH key exchange to derive a shared key. All subsequent messages are encrypted with XSalsa20-Poly1305 (NaCl `box`). The wire format is `[24-byte nonce][ciphertext]`, base64-encoded as a WebSocket text frame.
The relay sees only: IP addresses, timing, message sizes, session IDs, and the plaintext `e2ee_hello` / `e2ee_ready` handshake frames (which contain only public keys). It cannot read message contents, forge messages, or derive encryption keys from observing the handshake.
### Why the relay can't attack you
The daemon requires a valid cryptographic handshake before processing any commands. A compromised relay cannot:
- **Impersonate the daemon to your phone** — Without the daemon's secret key, it cannot derive the shared key, so any traffic it injects fails authenticated decryption on the phone
- **Send commands as you** — The daemon only accepts traffic that decrypts and authenticates under a shared key derived with its own secret key. The phone's keypair is ephemeral per connection, so there is no persistent phone-side secret to steal; protection comes from the daemon's secret key never leaving the daemon.
- **Read your traffic** — All messages are encrypted with XSalsa20-Poly1305 (NaCl box) after the handshake
- **Forge messages** — NaCl box provides authenticated encryption; tampered messages are rejected
- **Replay old messages across sessions** — Each session derives fresh encryption keys, so ciphertext from one session cannot be replayed into another session. Within a live session, replay protection is not yet implemented; the protocol uses random nonces and does not track nonce reuse or message counters.
### Trust model
The QR code or pairing link is the trust anchor. It contains the daemon's public key, which is required to establish the encrypted connection. Treat it like a password — don't share it publicly.
## Local daemon trust boundary
By default, the daemon binds to `127.0.0.1`. With no password configured, the local control plane is trusted by network reachability — anything that can reach the daemon socket can control the daemon. This is the same security model Docker documents for its daemon: the security boundary is access to the socket or listening address.
The daemon also supports an optional shared-secret password (set via `auth.password` in `config.json` or the `PASEO_PASSWORD` env var; stored bcrypt-hashed). When configured, every HTTP request must carry `Authorization: Bearer <password>` and every WebSocket upgrade must include a `Sec-WebSocket-Protocol: paseo.bearer.<password>` subprotocol. Browser WebSocket cannot set custom headers, which is why the token rides in the subprotocol. Health (`GET /api/health`) and CORS preflight (`OPTIONS`) are exempt. The password is intended for direct-TCP exposure (e.g. `tcp://host:port?ssl=true&password=...`); it is **not** a substitute for the relay's E2E encryption when traversing untrusted networks.
Connected clients are trusted operators of the daemon user. File previews follow that authority: a preview request may read any regular file the daemon process can read, while keeping path normalization and symlink checks in the daemon file service. Workspace-relative paths remain a UI convenience, not a security boundary.
If you expose the daemon beyond loopback, such as by binding to `0.0.0.0`, forwarding it through a tunnel or reverse proxy, or publishing it from a Docker container, you are responsible for restricting and securing that access. Setting a password is strongly recommended in that case.
In Docker, the official image runs the daemon and agents as the non-root
`paseo` user by default. Mounted workspaces and credentials are still fully
available to anything the agents run inside the container.
For remote access, use the relay connection. It is the supported path for reaching the daemon off-machine, and it adds end-to-end encryption plus a pairing handshake before commands are accepted.
Host header validation and CORS origin checks are defense-in-depth controls for localhost exposure. They help block DNS rebinding and browser-based attacks, but they do not replace network isolation.
## DNS rebinding protection
CORS is not a complete security boundary. It controls which browser origins can make requests, but does not prevent a malicious website from resolving its domain to your local machine (DNS rebinding).
Paseo validates the `Host` header on every HTTP request and every WebSocket upgrade against an allowlist (Vite-style semantics). By default, only `localhost`, `*.localhost`, and any literal IP address (IPv4 or IPv6) are accepted. Additional hostnames can be configured via `hostnames` in `config.json` or the `PASEO_HOSTNAMES` env var (comma-separated; entries beginning with `.` match a domain and its subdomains; the value `true` disables the allowlist entirely). Requests with unrecognized hosts are rejected with `403 Host not allowed`.
## Agent authentication
Paseo wraps agent CLIs (Claude Code, Codex, OpenCode) but does not manage their authentication. Each agent provider handles its own credentials. Paseo never stores or transmits provider API keys. Agents run in your user context with your existing credentials.
## Reporting vulnerabilities
If you discover a security vulnerability, please report it privately by emailing hello@moboudra.com. Do not open a public issue.