fix(security): enforce API_SERVER_KEY for non-loopback binding

Add is_network_accessible() helper using Python's ipaddress module to
robustly classify bind addresses (IPv4/IPv6 loopback, wildcards,
mapped addresses, hostname resolution with DNS-failure-fails-closed).

The API server connect() now refuses to start when the bind address is
network-accessible and no API_SERVER_KEY is set, preventing RCE from
other machines on the network.

Co-authored-by: entropidelic <entropidelic@users.noreply.github.com>
This commit is contained in:
entropidelic 2026-04-10 16:40:54 -07:00 committed by Teknium
parent 2a6cbf52d0
commit 989b950fbc
6 changed files with 188 additions and 8 deletions

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@ -269,10 +269,10 @@ For cloud sandbox backends, persistence is filesystem-oriented. `TERMINAL_LIFETI
| `WEBHOOK_PORT` | HTTP server port for receiving webhooks (default: `8644`) |
| `WEBHOOK_SECRET` | Global HMAC secret for webhook signature validation (used as fallback when routes don't specify their own) |
| `API_SERVER_ENABLED` | Enable the OpenAI-compatible API server (`true`/`false`). Runs alongside other platforms. |
| `API_SERVER_KEY` | Bearer token for API server authentication. Strongly recommended; required for any network-accessible deployment. |
| `API_SERVER_KEY` | Bearer token for API server authentication. Enforced for non-loopback binding. |
| `API_SERVER_CORS_ORIGINS` | Comma-separated browser origins allowed to call the API server directly (for example `http://localhost:3000,http://127.0.0.1:3000`). Default: disabled. |
| `API_SERVER_PORT` | Port for the API server (default: `8642`) |
| `API_SERVER_HOST` | Host/bind address for the API server (default: `127.0.0.1`). Use `0.0.0.0` for network access only with `API_SERVER_KEY` and a narrow `API_SERVER_CORS_ORIGINS` allowlist. |
| `API_SERVER_HOST` | Host/bind address for the API server (default: `127.0.0.1`). Use `0.0.0.0` for network access — requires `API_SERVER_KEY` and a narrow `API_SERVER_CORS_ORIGINS` allowlist. |
| `API_SERVER_MODEL_NAME` | Model name advertised on `/v1/models`. Defaults to the profile name (or `hermes-agent` for the default profile). Useful for multi-user setups where frontends like Open WebUI need distinct model names per connection. |
| `MESSAGING_CWD` | Working directory for terminal commands in messaging mode (default: `~`) |
| `GATEWAY_ALLOWED_USERS` | Comma-separated user IDs allowed across all platforms |

View file

@ -177,7 +177,7 @@ Authorization: Bearer ***
Configure the key via `API_SERVER_KEY` env var. If you need a browser to call Hermes directly, also set `API_SERVER_CORS_ORIGINS` to an explicit allowlist.
:::warning Security
The API server gives full access to hermes-agent's toolset, **including terminal commands**. If you change the bind address to `0.0.0.0` (network-accessible), **always set `API_SERVER_KEY`** and keep `API_SERVER_CORS_ORIGINS` narrow — without that, remote callers may be able to execute arbitrary commands on your machine.
The API server gives full access to hermes-agent's toolset, **including terminal commands**. When binding to a non-loopback address like `0.0.0.0`, `API_SERVER_KEY` is **required**. Also keep `API_SERVER_CORS_ORIGINS` narrow to control browser access.
The default bind address (`127.0.0.1`) is for local-only use. Browser access is disabled by default; enable it only for explicit trusted origins.
:::