{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "tinymce"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.7.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-05-27T21:29:43Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Impact\nA cross-site scripting (XSS) vulnerability was discovered in the URL sanitization logic of the core parser for `form` elements. The vulnerability allowed arbitrary JavaScript execution when inserting a specially crafted piece of content into the editor using the clipboard or APIs, and then submitting the form. However, as TinyMCE does not allow forms to be submitted while editing, the vulnerability could only be triggered when the content was previewed or rendered outside of the editor. This impacts all users who are using TinyMCE 5.7.0 or lower.\n\n### Patches\nThis vulnerability has been patched in TinyMCE 5.7.1 by improved URL sanitization logic.\n\n### Workarounds\nTo work around this vulnerability, either:\n- Upgrade to TinyMCE 5.7.1 or higher\n- Manually sanitize `form` URL attributes using a [TinyMCE node filter](https://www.tiny.cloud/docs/api/tinymce.html/tinymce.html.domparser/#addnodefilter).\n- Disable `form` elements in your content using the [invalid_elements](https://www.tiny.cloud/docs/configure/content-filtering/#invalid_elements) setting.\n\n#### Example: Sanitizing using a node filter\n```js\neditor.parser.addNodeFilter(\u0027form\u0027, function(nodes) {\n  nodes.forEach(function(node) {\n    if (node.attributes) {\n      node.attributes.forEach(function(attr) {\n        var name = attr.name;\n        var value = attr.value;\n        // Sanitize the attribute value here or remove it entirely\n        var sanitizedValue = ...;\n        node.attr(name, santizedValue);\n      });\n    }\n  });\n});\n```\n\n#### Example: Using invalid_elements\n```js\ninvalid_elements: \u0027form\u0027\n```\n\n### Acknowledgements\nTiny Technologies would like to thank Mikhail Khramenkov at Solar Security Research Team for discovering this vulnerability.\n\n### References\nhttps://www.tiny.cloud/docs/release-notes/release-notes571/#securityfixes\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an issue in the [TinyMCE repo](https://github.com/tinymce/tinymce/issues)\n* Email us at [infosec@tiny.cloud](mailto:infosec@tiny.cloud)",
  "id": "GHSA-5vm8-hhgr-jcjp",
  "modified": "2021-05-27T21:29:43Z",
  "published": "2021-05-28T19:18:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/tinymce/tinymce/security/advisories/GHSA-5vm8-hhgr-jcjp"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [],
  "summary": "Cross-site scripting vulnerability in TinyMCE"
}