CVE-2026-40602

hass-cli: Handling of user-supplied Jinja2 templates

MEDIUM
5.6
CVSS Score
Published: April 21, 2026 at 05:40 PM UTC
Updated: October 26, 2026 at 09:10 PM UTC
2 products affected across 1 vendorHome Assistant Command Line InterfaceHome Assistant Cli

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Severity
MEDIUM5.6
Exploit prediction
EPSS 0.1%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.0.0
Affected range stops below 1.0.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.6MEDIUMGitHub_M
Attack Vector
LOCAL
Complexity
HIGH
Privileges
HIGH
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-94CWE-1336

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