Only the latest 1.x release line receives security fixes while the project is pre-2.0. Pin to ^1.0.0 and we'll keep you covered.

Do not open a public GitHub issue for security reports.

Instead, email kenny.vaneetvelde@gmail.com with the subject prefix [tesseron-security] and a description of:

• The affected package(s) and version(s).
• A minimal reproduction (or at least a clear threat model).
• The impact you can demonstrate.

You'll get an acknowledgement within 72 hours. Once the issue is confirmed, we aim to ship a patched release within 14 days for high-severity issues and publish a coordinated advisory. Reporters are credited in the advisory unless they ask to stay anonymous.

Tesseron is a local-first SDK + gateway. Reports about the following are in scope:

• Authentication/authorization bypass on the gateway (claim-code flow, session scoping, cross-session data leaks).
• WebSocket origin-allowlist bypass.
• MCP protocol parsing / handshake issues (malformed JSON-RPC causing DoS, memory exhaustion, RCE).
• Schema-validation bypass that lets unvetted input reach handlers.
• Secret leakage via logs, error messages, or the resource manifest.
• Vulnerabilities in the published npm tarballs themselves (e.g. malicious postinstall scripts — we don't ship any).

Out of scope:

• Vulnerabilities in third-party dependencies unless Tesseron's usage makes them exploitable. File those upstream and let us know so we can bump.
• Denial-of-service via obviously pathological inputs (e.g. 100 MB JSON bodies on localhost). The gateway is a local-machine process; abuse of it requires local execution, which is an outside-scope threat model.
• Attacks that require the user to install a malicious MCP client.