MeshHood is experimental research software. It is not certified emergency infrastructure. Do not rely on it as your only way to call for help.
| Layer | Mechanism |
|---|---|
| Transport | AES-256-GCM over a neighborhood shared key (all wire traffic) |
| Direct messages | X25519 ECDH per peer pair; payload sealed inside encrypted envelope |
| Reputation / groups | Ed25519 signatures on kudos, profiles, admin actions |
| Relay privacy | Sealed DMs are blind-forwarded; relays see only opaque blobs |
| ICE card | Stored locally; attached only to your own emergency broadcast |
- Neighborhood key is derived from a demo passphrase baked into the app and Python tools. Anyone with the repo can decrypt neighborhood traffic. Production builds need per-neighborhood provisioning (QR code, HOA invite, etc.).
- No forward secrecy on the shared neighborhood key.
- No authentication of the mesh itself — a malicious neighbor with the key can inject traffic.
- BLE/WiFi range limits who can join your mesh; this is a feature and a boundary.
Cryptographic keys and mesh state live in app-private storage (SharedPreferences). Android backup is disabled (allowBackup=false) so keys are not copied to Google cloud backup.
Open a GitHub Security Advisory or email the maintainer for sensitive reports.