Trix: Stored XSS via HTMLParser attribute injection on paste

Description

The 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="{}".

Recommendation

Update the trix package to the latest compatible version. Followings are version details:

• Affected version(s): < 2.1.18
• Patched version(s): 2.1.18

References

• GHSA-53g2-mvcc-q9x3
• CVE-2026-73428
• CWE-79
• CAPEC-310
• OWASP 2021-A3
• OWASP 2021-A6

Related Issues

• Unhead has XSS bypass in `useHeadSafe` via attribute name injection and case-sensitive protocol check - CVE-2026-31860
• OneUptime: Stored XSS via Mermaid Diagram Rendering (securityLevel: "loose") - CVE-2026-32308
• TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes - CVE-2026-55661
• Svelte: XSS via HTML Comment Injection in SSR Error Boundary Hydration Markers - CVE-2026-27902

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Tags:

npm

trix