Craft CMS 4.0.0 before 4.18.7 and 5.0.0 before 5.10.14 RCE via actionCacheUpdates Behavior Injection

{
  "id": "99ffc62c206f46ebf7cdfafc66201bbd9995b493865a1c6224c99c5924f3cc1b",
  "url": "https://osv.dev/vulnerability/CVE-2026-109308",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Craft CMS 4.0.0 before 4.18.7 and 5.0.0 before 5.10.14 RCE via actionCacheUpdates Behavior Injection",
    "summary": "Craft CMS 4.0.0 before 4.18.7 and 5.0.0 before 5.10.14 passes the raw 'updates' request parameter in AppController::actionCacheUpdates to UpdatesModel without Component::cleanseConfig(), allowing behavior and event-handler injection. Authenticated control panel users with the performUpdates permission or Updates-utility access can supply 'as' or 'on' keys, such as an AttributeTypecastBehavior gadget, to execute arbitrary code.",
    "evidence": "osv:CVE-2026-109308",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-109308",
      "aliases": [
        "CVE-2026-109308",
        "GHSA-5m2g-hhqr-84pc"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/craftcms/cms",
              "type": "GIT",
              "events": [
                {
                  "introduced": "982efcd14d7e93a1a54f0905b61f242de6b53d8a"
                },
                {
                  "fixed": "565b88afb88df790c5465bcbb0a0b8aef2903dd2"
                },
                {
                  "introduced": "f6a8fb685d44e387435825e3a96809eeda4973a6"
                },
                {
                  "fixed": "6804f92fbdd93c3a3fb40f15bcd76a406e97634d"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "4.0.0"
                      },
                      {
                        "fixed": "4.18.7"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "introduced": "5.0.0"
                      },
                      {
                        "fixed": "5.10.14"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-109308.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:37.643480158Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/109xxx/CVE-2026-109308.json",
        "https://github.com/craftcms/cms/security/advisories/GHSA-5m2g-hhqr-84pc",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-109308",
        "https://www.vulncheck.com/advisories/craft-cms-4.0.0-before-4.18.7-and-5.0.0-before-5.10.14-rce-via-actioncacheupdates-behavior-injection"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-94"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/109xxx/CVE-2026-109308.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-109308",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504974,
  "published_at": "2026-10-12T16:05:04.666+00:00"
}