Containly talks to the Docker socket — that is equivalent to root on the host. Treat a Containly instance as being as sensitive as the host itself.

Please do not report vulnerabilities through public issues. Email support@containly.ch or use GitHub's private "Security Advisories". We aim to acknowledge reports within 72 hours.

Security fixes are provided for the latest released minor version.

• Auth: Argon2id password hashing, login rate limiting, timing-equalized password verification, optional two-factor authentication (TOTP + recovery codes).
• Sessions: HttpOnly/SameSite cookies, CSRF tokens, server-side session table.
• Secrets at rest: endpoint TLS/SSH credentials and TOTP secrets are AES-256-GCM encrypted (master key in data/ with 0600).
• Transport: Helmet headers incl. a strict CSP; HSTS/secure cookies behind TLS.
• Input: end-to-end schema validation (Zod) on every endpoint; path-traversal protection on all stack file operations.
• Audit: all security-relevant actions are logged.
• Backups: passphrase-encrypted (scrypt + AES-256-GCM).

1. Never expose without TLS. Put Containly behind a reverse proxy (Traefik/Caddy/nginx) with HTTPS + HSTS, set CONTAINLY_SECURE_COOKIES=true, and bind the port locally only (127.0.0.1:8420).
2. Use the socket proxy instead of mounting the socket directly. Use the bundled docker-socket-proxy (profile hardened) and add a TCP endpoint on the internal network — this limits the Docker API to what's needed and blocks e.g. Swarm / system shutdown.
3. Container hardening (compose):

   security_opt: ["no-new-privileges:true"]
   cap_drop: ["ALL"]
   read_only: true
   tmpfs: ["/tmp"]

   (Keep the direct socket mount read-only, :ro.)
4. Enable two-factor for every admin.

5. Least privilege for TCP endpoints: use the socket proxy on remote hosts too; scope TLS client certificates tightly.
6. Network segmentation: run Containly and the Docker hosts on a separate, non-public network.

7. Keep Containly up to date. Updates show up in the app and install with one click (automatic rollback if the new version is not healthy).
8. Scan your images: run the built-in Trivy scans on a schedule and act on critical findings.
9. Keep backups encrypted and offline — they contain the master key.

• The agent-less helper container on remote hosts mounts that host's Docker socket (required for deploys). Anyone with TCP Docker access is already root-equivalent, so no new privilege is introduced, but the standing container is a foothold and should be monitored accordingly.