CVE-2026-40602

hass-cli: Handling of user-supplied Jinja2 templates

State: Published
Severity: 5.6 Medium
Published: Apr 21, 2026
Updated: Apr 21, 2026
Reserved: Apr 14, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	5.6 Medium	CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N	GitHub_M

Weaknesses

CWE-94 Improper Control of Generation of Code ('Code Injection')
CWE-1336 Improper Neutralization of Special Elements Used in a Template Engine

Affected Products

Product	Versions
home-assistant-clihome-assistant-ecosystem	< 1.0.0Affected

References

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