This page is how to report a vulnerability. How the integration protects what it replicates — snapshot signing, TLS, sensitive domains, datastore credentials — is docs/REFERENCE-security.md.

Do not open a public issue. Use GitHub's private advisory form: Security → Report a vulnerability on this repository.

If that is unavailable to you, open an issue containing only "security report, please provide a private channel" and nothing else — no detail, no reproduction steps, no configuration.

You should get an acknowledgement within a week. If you do not, assume the message was lost rather than ignored, and chase it.

This integration is not a thermostat card. On a normal installation it:

• runs scripts as root on two machines, through a systemd timer that starts and stops Home Assistant and claims USB devices;
• holds credentials for a shared datastore that both nodes read and write;
• decides which of two machines is in charge of a house — its alarm, its locks, its heating.

A defect that lets somebody influence the lease decides who controls the building. Please treat it accordingly.

• Anything that lets an unauthorised party take, hold or influence the cluster lease.
• Anything that causes credentials, the cluster secret, or TLS material to be written where they should not be — logs, diagnostics, the bundle, the replicated fileset.
• Anything that lets snapshot content be forged or replayed such that a promoted node restores state it was never sent. Entries are signed for this reason; a way around that signature is a vulnerability.
• Anything that causes the promotion scripts to execute content an attacker controls.
• Privilege escalation through the generated bundle or install.sh.

Not because it does not matter, but because it is already written down and is a property of the design rather than a defect in it:

• Both nodes run automations during the overlap window. There is no automation leader election, deliberately. See docs/KNOWN-LIMITATIONS.md.
• A promoted standby has no radios attached to the other machine, and one radio never fails over at all.
• Anyone holding the datastore credential can read any namespace. The namespace is an organisational label, not a security boundary — said plainly in const.py where it is validated.
• The restore writes Home Assistant's state machine; it does not command devices. A restored "on" is not a switch being turned on.
• Findings from a scanner with no demonstrated impact on the above.

Please say which tool and include the finding verbatim. Several dependency advisories against this project are in packages pinned by Home Assistant itself, which this repository cannot upgrade independently — scripts/audit_deps.py reports those separately for exactly that reason, and a report that repeats one is still welcome, just already known.

The Download diagnostics button produces a file with secrets, hostnames, paths and URLs withheld, using an allowlist so that settings added in later releases are withheld by default rather than published by accident. It is handed to you as a download rather than uploaded on your behalf so that you can read it before deciding.

🚨 Home Assistant's logs are not redacted for you. They contain entity names, and occasionally tokens. Read them before pasting them into a public issue.