GitHub Advisoryadvisory · Packagist

GHSA-45fj-fvmm-xcc5 Concrete CMS has a stored Cross-site Scripting (XSS) vulnerability

MEDIUM Published 2026-03-04 Modified 2026-03-04 Official page ↗
Aliases
CVE-2026-3240
Ecosystem
Packagist
Packages
concrete5/concrete5
Severity
Moderate
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Weaknesses
CWE-79
Reviewed
2026-03-04

Affected packages

• Packagist concrete5/concrete5: < 9.4.8 → fixed in 9.4.8

Description

In Concrete CMS below version 9.4.8, a user with permission to edit a page with element Legacy form can perform a stored XSS attack towards high-privilege accounts via the Question field.  The Concrete CMS security team thanks minhnn42, namdi and quanlna2 from VCSLab-Viettel Cyber Security for reporting.

Related

Alias · CVE (1)

  • CVE-2026-3240 In Concrete CMS below version 9.4.8, a user with permission to edit a page with element Legacy form can perform a stored XSS attack towards… vulnerability

Weakness · CWE (1)

  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness

References