CVE-2026-23891: Decidim has a cross-site scripting (XSS) in user name

April 13, 2026 (updated April 27, 2026)

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.

References

github.com/advisories/GHSA-fc46-r95f-hq7g
github.com/decidim/decidim
github.com/decidim/decidim/releases/tag/v0.30.5
github.com/decidim/decidim/releases/tag/v0.31.1
github.com/decidim/decidim/security/advisories/GHSA-fc46-r95f-hq7g
nvd.nist.gov/vuln/detail/CVE-2026-23891

Code Behaviors & Features

Detect and mitigate CVE-2026-23891 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →