Is CVE-2026-8411 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-8411 being exploited in the wild.

How severe is CVE-2026-8411?

Medium severity, with a CVSS score of 4, published 21 May 2026.

Which products and versions are affected?

concrete5/concrete5 (Packagist) >= 9.0.0RC1, < 9.5.1, ECOSYSTEM:introduced=9.0.0RC1,fixed=9.5.1.

Is there a fix for CVE-2026-8411?

Yes. concrete5/concrete5 (Packagist): upgrade to 9.5.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-8411 attacked?

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

Am I affected by CVE-2026-8411?

Check whether you run concrete5/concrete5 (Packagist) 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-2026-8411: Concrete CMS CSRF in bulk page deletion controller

Q: Is there a fix for CVE-2026-8411?

Yes. concrete5/concrete5 (Packagist): upgrade to 9.5.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-8411 attacked?

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

Q: Am I affected by CVE-2026-8411?

Check whether you run concrete5/concrete5 (Packagist) 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-2026-8411 · Severity: medium · CVSS 4 · Published 2026-05-21

Concrete CMS is a content management system used to build and manage websites. A security flaw in the bulk page deletion feature allows an attacker to trick an administrator into unintentionally deleting website pages. This occurs if the administrator visits a malicious link while logged into the CMS, potentially leading to unauthorized data loss or site disruption.

Technologies: concrete5/concrete5 (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2026-8411 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-8411 being exploited in the wild.
How severe is CVE-2026-8411?: Medium severity, with a CVSS score of 4, published 21 May 2026.
Which products and versions are affected?: concrete5/concrete5 (Packagist) >= 9.0.0RC1, < 9.5.1, ECOSYSTEM:introduced=9.0.0RC1,fixed=9.5.1.
Is there a fix for CVE-2026-8411?: Yes. concrete5/concrete5 (Packagist): upgrade to 9.5.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-8411 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-8411?: Check whether you run concrete5/concrete5 (Packagist) 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.

How to fix

concrete5/concrete5 (Packagist): upgrade to 9.5.1 or later
```
composer require concrete5/concrete5:^9.5.1
```

Technical details

A Cross-Site Request Forgery (CSRF) vulnerability exists in Concrete CMS within the 'concrete/controllers/dialog/page/bulk/delete' component. The application fails to properly validate CSRF tokens or implement sufficient SameSite cookie attributes for requests targeting the bulk delete functionality. An attacker can exploit this by crafting a malicious webpage or link that, when accessed by an authenticated administrator, triggers a background request to delete multiple pages. This vulnerability is mitigated by the requirement for user interaction (the victim must click a link) and specific timing/state requirements. The issue is addressed in version 9.5.1.

Affected products

Concrete CMS Concrete CMS 9.0.0RC1 through 9.5.0

Identifiers

CVE-2026-8411
GHSA-752x-23hp-jmv6

Timeline

2026-05-21: disclosed: NVD publication date
2026-05-22: advisory: GitHub Advisory published
2026-06-24: patched: Advisory updated with patch information for version 9.5.1

References

https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes

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