# CVE-2026-81919

## Summary

- **CVE ID:** CVE-2026-81919
- **Severity:** LOW
- **CVSS Score:** 2.3 (CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N)
- **CWE:** CWE-352
- **Published:** Sep 15, 2026
- **Last Modified:** Sep 15, 2026

## Description

Concrete CMS below 9.5.3 did not validate an anti-CSRF token on the block-arrangement backend endpoint (the arrange() action of Concrete\Controller\Backend\Page\ArrangeBlocks). The action enforced page-edit authorization but performed no token check, and its route accepted any HTTP method, so an attacker could induce a signed-in content editor into loading an attacker-controlled page that auto-submitted a cross-site request and reordered or moved blocks in the draft version of a page the victim was permitted to edit. The default null cookie SameSite configuration let the victim's session cookie accompany the forged request. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.

## Affected Products

- Concrete CMS — Concrete CMS (5.0.0)

## References

- [CNA](https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.17%
- **EPSS Percentile:** 6.1

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-17._