Vulnerability Description
In Concrete CMS below CMS 9.5.3, the save_control action in the Express entities forms dashboard controller did not validate the anti-CSRF token. By causing an authenticated administrator to submit a forged cross-site request, a remote attacker without credentials could write attacker-controlled headline and body values to an existing Express form Text control. Those values were emitted without output encoding by the Express form Text element, so the injected markup executed as persistent JavaScript for any administrator who later opened the affected entry, resulting in stored cross-site scripting. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 7.7 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Concretecms | Concrete Cms | < 9.5.3 |
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-81897?
CVE-2026-81897 is a vulnerability with a CVSS score of 5.4 (MEDIUM). In Concrete CMS below CMS 9.5.3, the save_control action in the Express entities forms dashboard controller did not validate the anti-CSRF token. By causing an authenticated administrator to submit a ...
How severe is CVE-2026-81897?
CVE-2026-81897 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-81897?
Check the references section above for vendor advisories and patch information. Affected products include: Concretecms Concrete Cms.