Sleeper controls an existing browser session and can therefore handle highly sensitive page content. Please do not disclose a vulnerability in a public issue, discussion, pull request, or chat transcript.

Use GitHub's private vulnerability reporting / Security Advisory form for the Sleeper repository. Include the affected version or commit, the smallest reproduction that demonstrates the issue, and the security impact. If private reporting is unavailable while the repository is being prepared, contact the maintainer privately through the repository account and do not attach live cookies, tokens, passwords, screenshots, or customer data.

We will acknowledge a report when it is received, keep the report private while a fix is prepared, and coordinate disclosure after users have a fix.

Reports involving extension permissions, page-to-extension message boundaries, daemon authentication, Tailscale setup, cross-origin access, credential or screenshot exposure, command authorization, and package or installer integrity are in scope. Denial-of-service reports without a confidentiality or integrity impact may be handled as ordinary bugs.

The daemon accepts WebSocket connections only from genuine moz-extension:// / chrome-extension:// origins (webpages can never present one) that also prove possession of the local daemon token. By default the first extension to pair is pinned on disk; later connections from a different extension ID are rejected, which limits a stray or attacker-installed dev build from silently attaching to an existing daemon. Set SLEEPER_ALLOW_ANY_EXTENSION=false with SLEEPER_ALLOWED_EXTENSION_IDS for a fixed allowlist in managed environments. See docs/commands.md for the exact variables.

The latest release and the current default branch are supported. Development builds are not a secure update channel and should be used only with test profiles and test accounts.

Never publish the staging repository, its Git history, local analysis state, or build output as part of a security report. Public release preparation uses the history-free export procedure in docs/publication.md.