CVE-2026-47423 DOMPurify XSS via `selectedcontent` re-clone
DOMPurify fails to sanitize selectedcontent elements, allowing attackers to inject XSS payloads that execute in the victim's browser.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-47423?
CVE-2026-47423 is a high-severity cross-site scripting vulnerability in cure53 DOMPurify, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. In 3.4.4, DOMPurify allowed selectedcontent by default, allowing browsers to re-clone an XSS payload after sanitization so that unsanitized markup inside <selectedcontent> is returned. This issue is fixed in version 3.4.5.
Weakness: CWE-79
Which versions are affected by CVE-2026-47423?
2 open source packages ship an affected version, including dompurify. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
dompurify npm | From 3.4.4 | 3.4.5 |
dompurify npm | From 3.4.4 | 3.4.5 |
Products include Cure53 Dompurify.
How do I fix CVE-2026-47423?
Upgrade dompurify to 3.4.5 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-47423 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47423 exists.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in cure53 DOMPurify
- CVE-2024-47875 DOMPurify nesting-based mXSS
- CVE-2024-48910 DOMPurify vulnerable to tampering by prototype polution
- CVE-2024-45801 Tampering by prototype polution in DOMPurify
- CVE-2026-49978 DOMPurify IN_PLACE Sanitization Bypass via Attached Shadow Root Inside <template>.content
- CVE-2026-49458 DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks
Sources
Also known as DEBIAN-CVE-2026-47423, GHSA-87xg-pxx2-7hvx, UBUNTU-CVE-2026-47423.