CVE-2026-8353
Description
Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.
How to fix
- concretecms concrete_cms9.5.1 or later
- concrete5/concrete59.5.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| concretecms concrete_cms | 9.0 ≤ v < 9.5.1 | 9.5.1 |
| concrete5/concrete5Packagist | 9.0.0RC.1 ≤ v < 9.5.1 | 9.5.1 |
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Attack Surface Management
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