CVE-2026-45414: Decidim JWT authentication replay across organizations

CVE-2026-45414 · Severity: high · CVSS 8.5 · Published 2026-08-06

Decidim, a popular open-source platform for participatory democracy, is affected by a security flaw in how it handles multi-tenant authentication. In environments hosting multiple organizations, a security token issued for one organization can be reused to access private data in another organization. This could allow an attacker with administrative access in one group to view sensitive participant details or modify data in a completely separate group on the same server.

Technologies: Decidim, decidim (RubyGems). Vendors: Decidim, RubyGems.

Quick answers

Is CVE-2026-45414 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-45414 being exploited in the wild.
How severe is CVE-2026-45414?
High severity, with a CVSS score of 8.5, published 6 August 2026.
Which products and versions are affected?
Decidim < 0.31.5, >= 0.32.0.rc1, < 0.32.0; decidim (RubyGems) ECOSYSTEM:introduced=0,fixed=0.31.5.
Is there a fix for CVE-2026-45414?
Yes. decidim (RubyGems): upgrade to 0.31.5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-45414 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-45414?
Check whether you run Decidim or decidim (RubyGems) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • decidim (RubyGems): upgrade to 0.31.5 or later
    bundle update decidim

Technical details

Decidim is vulnerable to an authentication bypass (CWE-287) due to insufficient binding of JSON Web Tokens (JWT) to specific organization contexts in multi-tenant deployments. The root cause is that the API authentication strategy trusts a valid JWT principal without verifying that the principal belongs to the organization associated with the request's host header. An attacker with a valid JWT for one organization can replay that token against the API of a different organization on the same instance. This allows unauthorized access to admin-only GraphQL fields like 'participantDetails' and sensitive mutation paths such as 'proposal.answer'. The issue is fixed in versions 0.31.5 and 0.32.0.

Affected products

  • decidim decidim < 0.31.5, >= 0.32.0.rc1, < 0.32.0

Identifiers

  • CVE-2026-45414
  • GHSA-r3v7-5x4c-c69q

Timeline

  • 2026-04-29: other: Initial fix pull request submitted
  • 2026-05-10: patched: Final patches merged into development branch
  • 2026-07-13: advisory: GitHub Advisory published

References

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