CVE-2026-40602: Home-Assistant-Ecosystem Home Assistant Command-Line Interface

Medium severity, CVSS 5.6. EPSS: 0.1% chance of exploitation in the next 30 days.

The Home Assistant Command-line interface (hass-cli) is a command-line tool for Home Assistant. Up to 1.0.0 of home-assitant-cli an unrestricted environment was used to handle Jninja2 templates instead of a sandboxed one. The user-supplied input within Jinja2 templates was rendered locally with no restrictions. This gave users access to Python's internals and extended the scope of templating beyond the intended usage. This vulnerability is fixed in 1.0.0.

Affected products

Published 2026-04-21. Last modified 2026-06-17.