CVE-2026-23891

Decidim is a participatory democracy framework. In versions below 0.30.5 and 0.31.0.rc1 through 0.31.0, a stored code execution vulnerability in the user name field allows a low-privileged attacker to execute arbitrary code in the context of any user who passively visits a comment page, resulting in high confidentiality and integrity impact across security boundaries. This issue has been fixed in versions 0.30.5 and 0.31.1.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/decidim/decidim/releases/tag/v0.30.5	Product Release Notes
https://github.com/decidim/decidim/releases/tag/v0.31.1	Product Release Notes
https://github.com/decidim/decidim/security/advisories/GHSA-fc46-r95f-hq7g	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:decidim:decidim::::::ruby::*
	cpe:2.3:a:decidim:decidim::::::ruby::*

History

22 Apr 2026, 16:40

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.7
CPE		cpe:2.3:a:decidim:decidim::::::ruby::*
First Time		Decidim Decidim decidim
References	~~() https://github.com/decidim/decidim/releases/tag/v0.30.5 -~~	() https://github.com/decidim/decidim/releases/tag/v0.30.5 - Product, Release Notes
References	~~() https://github.com/decidim/decidim/releases/tag/v0.31.1 -~~	() https://github.com/decidim/decidim/releases/tag/v0.31.1 - Product, Release Notes
References	~~() https://github.com/decidim/decidim/security/advisories/GHSA-fc46-r95f-hq7g -~~	() https://github.com/decidim/decidim/security/advisories/GHSA-fc46-r95f-hq7g - Vendor Advisory

13 Apr 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-13 17:16

Updated : 2026-04-22 16:40

NVD link : CVE-2026-23891

Mitre link : CVE-2026-23891

CVE.ORG link : CVE-2026-23891

JSON object : View

Products Affected

decidim

decidim

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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