CVE-2026-81926 Cross-site scripting in Concrete CMS

Low 2.0 Published 15 Sep 2026 Updated 16 Sep 2026

Attackers can execute arbitrary scripts in an editor's browser session via unescaped page paths in the location panel dialog.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2026-81926?

CVE-2026-81926 is a low-severity cross-site scripting vulnerability in Concretecms Concrete Cms, published on 15 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

Official description

Concrete CMS 9.4.0 through 9.5.2 did not escape colliding page paths before rendering them in the location panel's duplicate-path confirmation dialog. The panel's check endpoint returned the submitted path unmodified in its JSON response, and client-side JavaScript inserted each value into the dialog as raw HTML, so a crafted page path executed script in the editor's authenticated browser session. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.0 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.

Weakness: CWE-79

Which versions are affected by CVE-2026-81926?

It affects 1 product.

Products include Concretecms Concrete Cms.

How do I fix CVE-2026-81926?

No fix has been published for CVE-2026-81926 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2026-81926 being exploited?

There is no known exploitation of CVE-2026-81926 in the wild and no public exploit code.

All Concretecms Concrete Cms vulnerabilities

Sources

Also known as GHSA-994m-pc89-jhp9.