Email security@archastro.ai with the affected version or commit, OS, terminal, reproduction steps, and impact. Please do not post vulnerabilities or credentials in public issues. When enabled, you can also use GitHub private vulnerability reporting.

Security fixes target the latest version on main; older versions do not have a separate maintenance commitment.

• ArchBrowse renders real websites and executes their JavaScript in Chromium. Sites can contact network services as in a browser. Local React projects and their dependencies must be trusted; this is a preview tool, not an isolation service for hostile code. Keep Chromium updated. Browser launch currently uses Playwright's defaults, which do not enable Chromium's sandbox.
• Local preview HTTP servers listen on 127.0.0.1. HTML mode serves files within its document root, including files other than the entry page. Choose a narrow --root and do not expose preview ports or CDP endpoints to untrusted networks.
• Named profiles persist cookies, localStorage, IndexedDB, and URLs. Treat session directories as credentials. Defaults live under ~/.local/share/archbrowse, with XDG/environment overrides and compatibility with older profile locations.
• Agent control can read page content, evaluate page JavaScript, and interact with logged-in sites. On Unix, sockets and their directories are owner-only; other processes running as your user can drive the session. Session names are identifiers, not authentication secrets. Windows named-pipe behavior has not been covered by the current Linux/macOS CI matrix.
• Background owners remain running after their launching CLI or attached viewer exits. Use sessions stop NAME to close them. Their viewer socket has the same Unix owner-only access boundary as agent control; a viewer can read pixels and send input.
• Screenshots, terminal transcripts, page snapshots, and test artifacts may contain sensitive content. Review them before sharing. The standard CI tests use local fixtures; external-site smoke tests are opt-in.

ArchBrowse has no application telemetry or hosted control service. Websites, browser downloads, npm/GitHub installation, and any agent provider you use have their own network behavior and data policies.