{"id":"GHSA-53p3-c7vp-4mcc","summary":"Trix is vulnerable to XSS through JSON deserialization bypass in drag-and-drop (Level0InputController)","details":"### Impact\n\nThe Trix editor, in versions prior to 2.1.18, is vulnerable to XSS when a crafted `application/x-trix-document` JSON payload is dropped into the editor in environments using the fallback Level0InputController (e.g., embedded WebViews lacking Input Events Level 2 support).\n\nThe `StringPiece.fromJSON` method trusted `href` attributes from the JSON payload without sanitization. An attacker could craft a draggable element containing a `javascript:` URI in the href attribute that, when dropped into a vulnerable editor, would bypass DOMPurify sanitization and inject executable JavaScript into the DOM.\n\nExploitation requires a specific environment (Level0InputController fallback) and social engineering (victim must drag and drop attacker-controlled content into the editor). Applications using server-side HTML sanitization (such as Rails' built-in sanitizer) are additionally protected, as the payload is neutralized on save.\n\n### Patches\n\nUpdate Recommendation: Users should upgrade to Trix editor version 2.1.18 or later.\n\n\n### References\n\nThe XSS vulnerability was responsibly reported by Hackerone researcher [newbiefromcoma](https://hackerone.com/newbiefromcoma).","aliases":["CVE-2026-73427"],"modified":"2026-09-10T03:50:59.722458333Z","published":"2026-03-29T15:22:17Z","database_specific":{"severity":"LOW","github_reviewed":true,"github_reviewed_at":"2026-03-29T15:22:17Z","nvd_published_at":null,"cwe_ids":["CWE-79"]},"references":[{"type":"WEB","url":"https://github.com/basecamp/trix/security/advisories/GHSA-53p3-c7vp-4mcc"},{"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"},{"type":"WEB","url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/action_text-trix/GHSA-53p3-c7vp-4mcc.yml"}],"affected":[{"package":{"name":"trix","ecosystem":"npm","purl":"pkg:npm/trix"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.1.18"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-53p3-c7vp-4mcc/GHSA-53p3-c7vp-4mcc.json"}},{"package":{"name":"action_text-trix","ecosystem":"RubyGems","purl":"pkg:gem/action_text-trix"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.18"}]}],"versions":["0.0.1","2.1.15","2.1.16","2.1.17"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-53p3-c7vp-4mcc/GHSA-53p3-c7vp-4mcc.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"}]}