GHSA-r3v7-5x4c-c69q is a high-severity (CVSS 8.5) CWE-639 vulnerability in decidim. A fix is available for decidim — see the affected versions and patch details below.
Decidim: JWT-backed authentication can be replayed across organizations
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-r3v7-5x4c-c69q.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-r3v7-5x4c-c69q plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
decidim💎decidimReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Description
A JWT issued to an Org 1 account is accepted on the Org 2 API and can read the admin-only GraphQL participantDetails field for an Org 2 participant. The same trust-boundary problem also affects API-user authentication: an Org 1 API user can use a JWT on the Org 1 host and replay that JWT to the Org 2 API to read Org 2 participant personal data and reach Org 2's proposal.answer mutation path.
Technical description
The current host selects the Decidim organization context, but JWT-backed API authentication is not sufficiently bound to that host organization. As a result, the API can process a request in Org 2's context while still trusting an authenticated principal from Org 1.
Reproduction steps:
- Use an API key provided by the system administrator that is assigned to organization 1 to create the JWT token or get the JWT token shown in the response when logged in as the organization admin.
- When using this JWT token it is possible to retrieve details from other organisations. Notice the change of the host header in the request below to that of another tenant
org2.localhost:3001
Note that using a participant-generated JWT did not allow showing these results.
Impact
A JWT issued for one organization can be replayed successfully against another organization's API and used to retrieve sensitive details from that organization.
Patches
See https://github.com/decidim/decidim/pull/16673 and https://github.com/decidim/decidim/pull/16756
Workarounds
Disable JWT credentials on system panel (/system)
References
OWASP A01:2021 Broken Access Control
Credits
This issue was discovered in a security audit organized by the Decidim Association and made by Radically Open Security against Decidim financed by NGI.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | decidim | all versions | 0.31.5bundle update decidim --conservative |
| 💎RubyGems | decidim | ≥ 0.32.0.rc1&&< 0.32.0 | 0.32.0bundle update decidim --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for decidim, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update decidim to 0.31.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r3v7-5x4c-c69q is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-r3v7-5x4c-c69q can be triaged on real exposure rather than presence alone.
Tailored to GHSA-r3v7-5x4c-c69q. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-r3v7-5x4c-c69q in your dependencies?
O3 Security finds GHSA-r3v7-5x4c-c69q across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.