Home Assistant is open source home automation software that puts local control and privacy first. Home Assistant apps (formerly add-ons) configured with host network mode expose unauthenticated endpoints bound to the internal Docker bridge interface to the local network. On Linux, this configuration does not restrict access to the app as intended, allowing any device on the same network to reach these endpoints without authentication. Home Assistant Supervisor 2026.03.02 addresses the issue.
In host network mode, Home Assistant applications bind their endpoints to the internal Docker bridge interface. On Linux systems, this configuration does not restrict access as intended — network isolation does not work correctly. As a result, any device present in the same local network can directly communicate with these endpoints, bypassing authentication mechanisms (CWE-923: improper restriction of communication channel to intended endpoints).
An attacker with access to the local network can gain unauthenticated access to functions exposed by Home Assistant applications, which may lead to complete compromise of confidentiality, integrity, and availability of the home automation system.
Home Assistant Supervisor must be updated to version 2026.03.02 or newer, which contains a fix eliminating the described issue. Details are available in the vendor's official security advisory.
Home Assistant Supervisor in versions prior to 2026.03.02, when applications (add-ons) are configured in host network mode and running on a Linux system.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H