Vulnerability 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 gave this vulnerability a CVSS v.4.0 score of 4.8 with 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 Thanks minhnn42, namdi and quanlna2 from VCSLab-Viettel Cyber Security for reporting.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Concretecms | Concrete Cms | < 9.4.8 |
Related Weaknesses (CWE)
References
- https://documentation.concretecms.org/9-x/developers/introduction/version-historRelease NotesPatchVendor Advisory
- https://github.com/concretecms/concretecms/pull/12826ExploitIssue TrackingVendor Advisory
FAQ
What is CVE-2026-3240?
CVE-2026-3240 is a vulnerability with a CVSS score of 4.8 (MEDIUM). 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...
How severe is CVE-2026-3240?
CVE-2026-3240 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-3240?
Check the references section above for vendor advisories and patch information. Affected products include: Concretecms Concrete Cms.