---
cve: "CVE-2026-41238"
severity: "MEDIUM"
cvss: 6.9
epss: "23%"
vendor: "cure53"
kev: false
exploited: false
published: "2026-04-23 16:16:26"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-11T21:58:55+02:00"
---

# CVE-2026-41238

> 6.9 MEDIUM · 🧪 PoC

## Beschreibung

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Versions 3.0.1 through 3.3.3 are vulnerable to a prototype pollution-based XSS bypass. When an application uses `DOMPurify.sanitize()` with the default configuration (no `CUSTOM_ELEMENT_HANDLING` option), a prior prototype pollution gadget can inject permissive `tagNameCheck` and `attributeNameCheck` regex values into `Object.prototype`, causing DOMPurify to allow arbitrary custom elements with arbitrary attributes — including event handlers — through sanitization. Version 3.4.0 fixes the issue.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Erforderlich | good |
| S Scope | Verändert | bad |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Gering | warn |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 5b16e0b892e82b1779d62b9928b43c4c4ff290b9 (Commit)

## Referenzen

- <https://github.com/cure53/DOMPurify/security/advisories/GHSA-v9jr-rg53-9pgp>
- <https://github.com/cure53/DOMPurify/releases/tag/3.4.0>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-41238) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_