CVE-2026-59178

ESPHome Device Builder Dashboard is a dashboard for the ESPHome home management software. Prior to version 1.0.12, the dashboard reads its authentication credentials from `$ESPHOME_USERNAME` and `$ESPHOME_PASSWORD`. Earlier versions, and the legacy `esphome` dashboard, read the bare `$USERNAME` and `$PASSWORD` instead. When the env vars were renamed the bare names were dropped with no fallback, so an operator who had protected their dashboard with `USERNAME` / `PASSWORD` (as the older getting started guide documented) loses authentication on upgrade and the dashboard starts open to anyone who can reach its port. The issue is fixed in 1.0.12. The bare `$USERNAME` / `$PASSWORD` are accepted again as a deprecated fallback so previously protected instances stay protected across the upgrade without operator intervention, with a loud deprecation warning at startup directing operators to rename them to `$ESPHOME_USERNAME` / `$ESPHOME_PASSWORD`. The fallback is gated on `$PASSWORD` being set and is only adopted as a pair, so the OS provided `$USERNAME` is never read on its own and the original collision footgun stays closed. A lone bare `$PASSWORD` with no username still fails loud as a cr