Vulnerabilities in pkg:npm/trix

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-53g2-mvcc-q9x3",
  "modified" : "2026-08-12T20:52:01Z",
  "published" : "2026-07-24T16:18:01Z",
  "aliases" : [ "CVE-2026-73428" ],
  "summary" : "Trix: Stored XSS via HTMLParser attribute injection on paste",
  "details" : "### Impact\n\nThe Trix editor, in versions prior to 2.1.18, is vulnerable to XSS when crafted HTML is pasted into the editor. The `HTMLParser` processed a mock attachment, a `<span>` carrying an empty `data-trix-attachment=\"{}\"`. The empty attachment object caused the element to bypass attachment handling, so its `data-trix-attributes` were applied to a plain string piece. The pre-2.1.18 `StringPiece.fromJSON` accepted the `href` without validation, so an attacker-supplied `javascript:` URI was carried into the document model and emitted verbatim into the serialized HTML, executing when the content was rendered and clicked.\n\nThis is a stored XSS in any application that accepts untrusted rich text through Trix and renders the serialized output to other users. Applications that apply server-side HTML sanitization, such as the Rails built-in sanitizer, are additionally protected because the payload is neutralized on save.\n\nThis vulnerability shares its fix with GHSA-53p3-c7vp-4mcc. Both are resolved by the `StringPiece.fromJSON` sanitization added in 2.1.18. This advisory covers the paste and HTMLParser entry vector, while GHSA-53p3-c7vp-4mcc covers the drag-and-drop path through the fallback Level0InputController.\n\n### Patches\n\nUsers should upgrade to Trix editor version 2.1.18 or later.\n\n### References\n\nThe vulnerability was responsibly reported by HackerOne researcher [newbiefromcoma](https://hackerone.com/newbiefromcoma).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "trix"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.1.18"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "action_text-trix"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.1.18"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/basecamp/trix/security/advisories/GHSA-53g2-mvcc-q9x3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/basecamp/trix/commit/9c0a993d9fc2ffe9d56b013b030bc238f9c0557c"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/basecamp/trix"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/basecamp/trix/releases/tag/v2.1.18"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-24T16:18:01Z",
    "nvd_published_at" : null
  }
}