Security

DSH Mobile is a remote control for the DeepSeek Harness. Understand the trust model before using it.

The harness has no authentication

The harness web server (dsh web) serves plain HTTP with a trust fence, not authentication:

• Every /api request is accepted only when its Host header is loopback or a configured trusted authority (LAN IP literals are auto-derived when the server binds 0.0.0.0).
• There are no tokens, cookies, or TLS. Any device on the same network can send requests with a trusted Host and drive the agent — including running commands on the host computer.

Consequences:

• Only bind the harness to 0.0.0.0 on networks you fully trust (home network, your own lab). Never on public or guest Wi-Fi.
• DSH Mobile shows a warning banner whenever you connect to a non-loopback host.
• Sensitive surfaces (settings, credentials, agent-preset authoring, host file pickers) remain loopback-only by harness design and are shown read-only over the network.

What DSH Mobile stores

• Remembered host addresses (host, port, display name) and app preferences, in app-private storage only.
• No session content is persisted to disk in v1 (chat history lives in memory and is re-fetched on connect).
• The app allows cleartext HTTP by necessity (the harness serves plain HTTP); see app/src/main/res/xml/network_security_config.xml.

What DSH Mobile connects to

Every connection is to a LAN endpoint you entered or picked from a scan, with one exception:

• The update check. On start the app asks api.github.com for this repository's latest release, over HTTPS, so it can tell you when a newer APK exists. It sends no identifying information beyond what any HTTPS request carries, and it is the only request that leaves your network. Turn it off in Settings → About → Check for updates; nothing else in the app contacts anything but the harness.
• Scanning probes only your own device's IPv4 /24, and only with a TCP connect followed by the harness's own host.describe.

Reporting a vulnerability

Report security issues privately, either through Report a vulnerability on the repository's Security tab or by email to sor@zyphite.com. Do not open a public issue for a vulnerability. Include what an attacker can do, the steps to reproduce it, the app and harness versions, and how the app was connected.

The harness having no authentication is the documented model above, not a vulnerability report worth sending. A way around the trust fence is.

Roadmap

Upstream harness improvements that would materially harden this setup are tracked as issues in this repository:

1. An authentication layer (pairing token) on the web server.
2. An explicit --lan flag (currently the CLI blocks --host 0.0.0.0).
3. mDNS advertisement for zero-touch, authenticated discovery.