CVE-2026-40870Network attack vector

Unauthenticated data disclosure via unchecked commentable query

Published Apr 21, 2026 · Updated Apr 21, 2026

Missing authorization in Decidim before 0.30.5 and 0.31.0.rc1 through 0.31.0 allows remote attackers to read nonpublic commentable resources. The root-level GraphQL commentable field returns all commentable resources without checking whether the requester has permission to view each resource. The API is public by default; forced organization authentication changes the gate to any permitted user, and disclosure matters only where commentable resources are private.

CVSS severity7.5
High
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Decidim before 0.30.5 and 0.31.0.rc1 through 0.31.0 allows remote attackers to read nonpublic commentable resources. The root-level GraphQL commentable field returns all commentable resources without checking whether the requester has permission to view each resource. The API is public by default; forced organization authentication changes the gate to any permitted user, and disclosure matters only where commentable resources are private.

The record

CVE
CVE-2026-40870
Published
Apr 21, 2026
Updated
Apr 21, 2026
Vendor
Decidim
Product
Decidim
Classifications
CWE-862, T1213
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 0.0.1, < 0.30.5
  2. Affected versionversion=> 0.31.0.rc1, < 0.31.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Decidim · Decidimversion=>= 0.0.1, < 0.30.5; version=> 0.31.0.rc1, < 0.31.1

Published CVSS scores

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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1213Data from Information Repositories

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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