The latest 0.x release on main receives security fixes. There are no long-term support branches yet.

Please use GitHub's private vulnerability reporting:

https://github.com/kai38/kai-webbridge/security/advisories/new

Do not open a public issue, discussion, or pull request that describes an unfixed vulnerability. Include:

• affected version or commit,
• operating system and Chrome version,
• a minimal reproduction,
• impact (what an attacker gains),
• whether the issue requires a malicious website, a local process, or physical access.

You can expect an acknowledgement within a few days. A fix and advisory will be published together; credit is given unless you prefer to stay anonymous.

In scope:

• the daemon (src/) — HTTP API, WebSocket hub, authentication, Origin guard, file writes, CLI;
• the extension (extension/) — debugger attachment, tool implementations, permission model, message handling;
• the agent skill (skill/) — instructions that could cause unsafe actions;
• packaging and install scripts.

Out of scope:

• vulnerabilities in Chrome or Chrome's debugger protocol,
• a compromised agent runtime or model provider,
• a user intentionally running the daemon with host: 0.0.0.0 or handing the token to an untrusted process,
• phishing or prompt-injection scenarios that rely on the agent ignoring its own instructions (report those as design feedback, not vulnerabilities).

• The daemon binds 127.0.0.1 by default and sends no telemetry.
• /command ignores requests that carry an Origin header (anti-CSRF).
• The optional bearer token protects both HTTP commands and the extension WebSocket.
• The extension requires the debugger permission, so it can read and modify any tab. This is disclosed in the README and docs/security.md.
• A second browser connection is refused with WebSocket close code 4409; a foreign extension protocol is refused with 4400.