What is CVE-2026-40870?

CVE-2026-40870 is a high-severity vulnerability in Decidim, classified under Missing Authorization. CVSS score: 7.5/10. Published 2026-04-21.

How severe is CVE-2026-40870?

High severity. CVSS v3 base score is 7.5 out of 10.

Auth bypass in Decidim

CVE-2026-40870

Decidim is a participatory democracy framework. Starting in version 0.0.1 and prior to versions 0.30.5 and 0.31.1, the root level `commentable` field in the API allows access to all commentable resources within the platform, without any pe…

Vulnerability class: Broken Access Control

EPSS: 0.000 (14.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Decidim — versions > 0.31.0.rc1, < 0.31.1, >= 0.0.1, < 0.30.5

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

https://github.com/decidim/decidim/security/advisories/GHSA-ghmh-q25g-gxxx (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-40870?: CVE-2026-40870 is a high-severity vulnerability in Decidim, classified under Missing Authorization. CVSS score: 7.5/10. Published 2026-04-21.
How severe is CVE-2026-40870?: High severity. CVSS v3 base score is 7.5 out of 10.