Decidim vulnerable to sensitive data disclosure

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

• CVE-2023-34090: 1.26% estimated exploitation activity in the next 30 days; percentile 69.64 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Note: added the actual report as a comment. Summary Decidim, a platform for digital citizen participation, uses a third-party library named Ransack for filtering certain database collections (e.g., public meetings). By default, this library allows filtering on all data attributes and associations. This allows an unauthenticated remote attacker to exfiltrate non-public data from the underlying database of a Decidim instance (e.g., exfiltrating data from the user table). Impact This issue may lead to Sensitive Data Disclosure. Patches The problem was patched in v0.27.3. Workarounds Disable or unpublish all meetings components from your application.

Published by the source

11 Jul 2023, 22:46 UTC

Last modified by the source

6 Nov 2023, 05:05 UTC

Source last checked

26 Oct 2026, 15:48 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-jm79-9pm4-vrw9

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# Patch Next advisory brief: CVE-2023-34090

Advisory: Decidim vulnerable to sensitive data disclosure
IDs: CVE-2023-34090, GHSA-jm79-9pm4-vrw9
Record: https://patchnext.com/advisories/cve-2023-34090 (revision 1, source checked 26 Oct 2026, 15:48 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: decidim 0.27.3; decidim-meetings 0.27.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- RubyGems decidim: affected >= 0.27.0, < 0.27.3; fixed in 0.27.3
- RubyGems decidim-meetings: affected >= 0.27.0, < 0.27.3; fixed in 0.27.3

## Suggested inspection (read-only)
- RubyGems decidim: check the installed version with your package manager.
- RubyGems decidim-meetings: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on decidim, decidim-meetings.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-jm79-9pm4-vrw9 (GitHub-reviewed advisory GHSA-jm79-9pm4-vrw9 lists affected ranges: RubyGems decidim >=0.27.0 =0.27.0 <0.27.3)

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