Security advisory

{
  "id": "1a71d2e7c189b2fd0ceb4601e8e5bc675ba1c3fae1e8ee50caceba4d64bf593c",
  "url": "https://osv.dev/vulnerability/CVE-2020-5809",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-5809",
    "summary": "A stored XSS vulnerability exists in Umbraco CMS <= 8.9.1 or current. An authenticated user can inject arbitrary JavaScript code into iframes when editing content using the TinyMCE rich-text editor, as TinyMCE is configured to allow iframes by default in Umbraco CMS.",
    "evidence": "osv:CVE-2020-5809",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2020-5809",
      "aliases": [
        "CVE-2020-5809",
        "GHSA-95qr-67rx-9pgh"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/umbraco/umbraco-cms",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "ca098e8a0190638712aefa807d6eb862f83aac4d"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:umbraco:umbraco_cms:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "8.9.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "release-8.9.1",
            "release-8.9.0",
            "release-8.9.0-rc",
            "release-8.1.0",
            "release-7.2.0-beta2",
            "release-7.2.0-beta",
            "release-7.1.4",
            "release-7.2.0-alpha",
            "release-7.1.3",
            "release-7.1.2",
            "release-7.1.1",
            "release-7.1.0",
            "release-7.1.0-RC",
            "release-7.0.0",
            "release-7.0.0-RC",
            "release-7.0.0-beta",
            "release-6.1.0-beta",
            "4.7.2",
            "Release-4.6.0",
            "Sprint-Juno-A",
            "Release-4.5.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-5809.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:43.682527091Z",
      "provider": "osv",
      "references": [
        "https://www.tenable.com/security/research/tra-2020-59"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-5809",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 435678,
  "published_at": "2020-12-30T16:15:12.32+00:00"
}