CVE-2026-40869: Decidim amendments can be accepted or rejected by anyone

April 14, 2026 (updated April 24, 2026)

The 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.

References

github.com/advisories/GHSA-w5xj-99cg-rccm
github.com/decidim/decidim
github.com/decidim/decidim/commit/1b99136a1c7aa02616a0b54a6ab88d12907a57a9
github.com/decidim/decidim/security/advisories/GHSA-w5xj-99cg-rccm
nvd.nist.gov/vuln/detail/CVE-2026-40869

Code Behaviors & Features

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