CVE-2026-3240: Concrete CMS has a stored Cross-site Scripting (XSS) vulnerability

medium Affects concrete5/concrete5. Feed 2026.10.29.3, updated 2026-10-29; published 2026-03-04.

Concrete CMS has a stored Cross-site Scripting (XSS) vulnerability

Package: concrete5/concrete5 Composer
Affected versions: <9.4.8
Fixed in: 9.4.8
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (12.7th percentile)
Published: 2026-03-04
Source: osv.dev

References

NVD record concrete5/concrete5 advisories

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Related advisories

CVE-2020-11476 high Unrestricted Uploads in Concrete5 same package: concrete5/concrete5
CVE-2017-7725 medium Concrete CMS vulnerable to cross-site scripting (XSS) same package: concrete5/concrete5
CVE-2026-6826 medium Concrete CMS is vulnerable to unauthenticated file usage disclosure same package: concrete5/concrete5
CVE-2012-5181 medium Concrete5 Vulnerable to Cross-Site Scripting (XSS) same package: concrete5/concrete5
CVE-2024-1247 low Concrete CMS vulnerable to stored XSS via the Role Name field same package: concrete5/concrete5
CVE-2023-48648 medium Concrete CMS allows unauthorized access because directories can be created with insecure p same package: concrete5/concrete5