CVE-2026-8353
Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in atomik theme
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.
INFO
Published Date :
May 22, 2026, 2:18 p.m.
Last Modified :
May 22, 2026, 2:18 p.m.
Remotely Exploit :
Yes !
Source :
ConcreteCMS
Affected Products
The following products are affected by CVE-2026-8353
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | LOW | ff5b8ace-8b95-4078-9743-eac1ca5451de |
Solution
- Update Concrete CMS to the latest version.
- Apply security patches for the Atomik theme.
- Review user roles and permissions.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-8353 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-8353 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 22, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:* versions from (including) 9.0 up to (excluding) 9.5.1 Added Reference Type ConcreteCMS: https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes Types: Release Notes, Vendor Advisory -
New CVE Received by ff5b8ace-8b95-4078-9743-eac1ca5451de
May. 22, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-79 Added Reference https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes