CVE-2024-39910: decidim XSS — Fix

Description

decidim is a Free Open-Source participatory democracy, citizen participation and open government for cities and organizations. The WYSWYG editor QuillJS is subject to potential XSS attach in case the attacker manages to modify the HTML before being uploaded to the server. The attacker is able to change e.g. to <svg onload=alert('XSS')> if they know how to craft these requests themselves. This issue has been addressed in release version 0.27.7. All users are advised to upgrade. Users unable to upgrade should review the user accounts that have access to the admin panel (i.e. general Administrators, and participatory space's Administrators) and remove access to them if they don't need it. Disable the "Enable rich text editor for participants" setting in the admin dashboard

Is your site exposed to CVE-2024-39910?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:N/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
decidim	decidim	< 0.27.7

References

Advisories & Patches

https://github.com/decidim/decidim/commit/47adca81cabea898005ec07b130b008f2a2be99f https://github.com/decidim/decidim/security/advisories/GHSA-vvqw-fqwx-mqmm

Frequently Asked Questions

What is CVE-2024-39910? +

decidim is a Free Open-Source participatory democracy, citizen participation and open government for cities and organizations. The WYSWYG editor QuillJS is subject to potential XSS attach in case the attacker manages to modify the HTML before being uploaded to the server. The attacker is able to change e.g. to <svg onload=alert('XSS')> if they know how to craft these requests themselves. This issue has been addressed in release version 0.27.7. All users are advised to upgrade. Users unable to upgrade should review the user accounts that have access to the admin panel (i.e. general Administrators, and participatory space's Administrators) and remove access to them if they don't need it. Disable the "Enable rich text editor for participants" setting in the admin dashboard It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2024-39910? +

CVE-2024-39910 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-39910? +

CVE-2024-39910 affects products from decidim, specifically: decidim. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-39910? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-40282

WeGIA is a web manager for charitable institutions. In versions prior to 3.6.10, a Stored Cross-Site Scripting (XSS) vulnerability allows …

CVE-2026-3317

Reflected Cross-Site Scripting (XSS) vulnerability in Navigate Content Management System. The vulnerability is present in the '/blog' endpoint because user …

CVE-2025-10354

Cross-Site Scripting (XSS) vulnerability reflected in Semantic MediaWiki. This vulnerability allows an attacker to execute JavaScript code in the victim's …

CVE-2026-41456

Bludit CMS prior to commit 6732dde contains a reflected cross-site scripting vulnerability in the search plugin that allows unauthenticated attackers …

CVE-2026-40872

mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the admin dashboard's Autodiscover …

CVE-2026-40878

mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the mailcow web interface …

CVE-2024-39910