Decidim vulnerabilities
Published CVEs affecting Decidim products: 4 record(s), with severity, exploitation and fixes.
CVE-2026-40870
High · 7.5
CWE-862 Apr 21, 2026
Decidim's comments API allows access to all commentable resources
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 permission checks. All Decidim instances are impacted that have not secured the `/api` endpoint. The `/api` endpoint is publicly available with the default configuration. Versions 0.30.5 and 0.31.1 fix the issue. As a workaround, limit the scope to only authenticated users by limiting access to the `/api` endpoint. This would require custom code or installing the 3rd party module `Decidim::Apiauth`. With custom code, the `/api` endpoint can be limited to only authenticated users. The same configuration can be also used without the `allow` statements to disable all traffic to the the `/api` endpoint. When considering a workaround and the seriousness of the vulnerability, please consider the nature of the platform. If the platform is primarily serving public data, this vulnerability is not serious by its nature. If the platform is protecting some resources, e.g. inside private participation spaces, the vulnerability may expose some data to the attacker that is not meant public. For those who have enabled the organization setting "Force users to authenticate before access organization", the scope of this vulnerability is limited to the users who are allowed to log in to the Decidim platform. This setting was introduced in version 0.19.0 and it was applied to the `/api` endpoint in version 0.22.0.
CVE-2026-40869
Medium · 6.5
CWE-266 Apr 21, 2026
Decidim amendments can be accepted or rejected by anyone
Decidim is a participatory democracy framework. Starting in version 0.19.0 and prior to versions 0.30.5 and 0.31.1, a vulnerability allows any registered and authenticated user to accept or reject any amendments. The impact is on any users who have created proposals where the amendments feature is enabled. This also elevates the user accepting the amendment as the author of the original proposal as people amending proposals are provided coauthorship on the coauthorable resources. Versions 0.30.5 and 0.31.1 fix the issue. As a workaround, disable amendment reactions for the amendable component (e.g. proposals).
CVE-2026-23891
High · 8.7
CWE-79 Apr 13, 2026
Decidim has a Cross-site scripting (XSS) vulnerability via user name field
Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a stored code execution vulnerability in the user name field allows a low-privileged attacker to execute arbitrary code in the context of any user who passively visits a comment page, resulting in high confidentiality and integrity impact across security boundaries. This issue has been fixed in versions 0.30.5 and 0.31.1.
CVE-2025-65017
Medium · 6.5
CWE-200 Feb 3, 2026
Decidim's private data exports can lead to data leaks
Decidim is a participatory democracy framework. In versions from 0.30.0 to before 0.30.4 and from 0.31.0.rc1 to before 0.31.0, the private data exports can lead to data leaks in case the UUID generation, causing collisions for the generated UUIDs. This issue has been patched in versions 0.30.4 and 0.31.0.