Is CVE-2026-81919 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-81919 being exploited in the wild.

How severe is CVE-2026-81919?

Medium severity, with a CVSS score of 4.3, published 15 September 2026.

Is there a fix for CVE-2026-81919?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-81919 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-81919?

Check whether you run Concrete CMS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-81919: Concrete CMS CSRF in block arrangement endpoint

CVE-2026-81919 · Severity: medium · CVSS 4.3 · Published 2026-09-15

Concrete CMS, a content management system used to build and manage websites, had a missing anti-CSRF token validation flaw in its page block arrangement feature. An attacker could trick a logged-in content editor into visiting a malicious webpage, which would automatically reorder or move content blocks on pages the victim could edit, potentially corrupting the page layout or losing work. The vulnerability required the victim to be already logged in and actively using the CMS.

Technologies: Concrete CMS. Vendors: Concrete CMS.

Quick answers

Is CVE-2026-81919 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-81919 being exploited in the wild.
How severe is CVE-2026-81919?: Medium severity, with a CVSS score of 4.3, published 15 September 2026.
Which products and versions are affected?: Concrete CMS below 9.5.3.
Is there a fix for CVE-2026-81919?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-81919 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-81919?: Check whether you run Concrete CMS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This is a Cross-Site Request Forgery (CSRF) vulnerability in the ArrangeBlocks backend controller's arrange() action. The vulnerable endpoint enforced page-edit authorization but failed to validate anti-CSRF tokens, while also accepting any HTTP method without restriction. An attacker can craft a malicious page containing an auto-submitting form that invokes the arrange() action with forged parameters. If a signed-in content editor visits the attacker's page, the victim's session cookie is sent with the request (due to the default null SameSite cookie configuration), allowing the attacker to reorder or move blocks in draft versions of pages the victim has edit permissions for. No patch availability information is explicitly stated in the advisory, though the vulnerability affects versions below 9.5.3.

Affected products

Concrete CMS Concrete CMS below 9.5.3

Timeline

2026-09-15: disclosed

References

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