CVE-2026-81918
Medium
Description
Concrete CMS below 9.5.3 is vulnerable to Stored XSS via the Date Format field in the Page Attribute Display block. A user with edit_page_contents permissions could store a payload which executes in the browser of any visitor who viewed a page where the block was configured to display a date-type attribute. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 4.8 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Oriol Ortiz for reporting.
SeverityMedium
CVSS4.8
Exploit probability17. percentile0.3%
Product
Concretecms Concrete Cms
PublishedSep 11, 2026
First seenSep 11, 2026
Weakness typeCWE-79Cross-site scripting (XSS)
How to fix
Update
- concretecms concrete_cms9.5.3 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| concretecms concrete_cms | v < 9.5.3 | 9.5.3 |
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