CVE-2026-23891 CRITICAL

CVE-2026-23891: Decidim has a Cross-site scripting (XSS) vulnerability via user name field

Vendor Decidim
Product decidim
Weakness CWE-79 · XSS
Published April 13, 2026
Last update April 14, 2026

CVSS base score

9.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 13, 2026 CVE published
April 14, 2026 Record updated