{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "9.0.0"
              },
              {
                "last_affected": "9.5.2"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "b3774abddd475b4ba98b637402506f7a5ebd90ea"
            },
            {
              "last_affected": "8fe9708072c3815a5df719b592e4b23b43b4ff7a"
            }
          ],
          "repo": "https://github.com/concretecms/concretecms",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "ConcreteCMS",
    "cwe_ids": [
      "CWE-352"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84432.json"
  },
  "details": "Concrete CMS 9 through  9.5.2 did not validate an anti-CSRF token in the Boards custom slot dialog controller (concrete/controllers/dialog/board/custom_slot.php) saveTemplate() action. The action created a board_slot_proxy Block and dispatched an AddCustomSlotToBoardCommand against a board instance while gating only on the per-resource canEditBoardContents() permission, so a crafted cross-site request could cause a user holding board-edit permission with an active session to write attacker-chosen slot and template data to a board under their own authority. The state-changing database write completed before any downstream rendering, so the forged request succeeded even when the HTTP response returned a non-200 status. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.3 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.",
  "id": "CVE-2026-84432",
  "modified": "2026-09-12T03:30:41.834842980Z",
  "published": "2026-09-10T19:19:34.223Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84432.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84432"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/concretecms/concretecms"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Concrete CMS 9 through  9.5.2 is vulnerable to CSRFin the Boards custom slot dialog controller"
}