---
cve: "CVE-2026-41240"
severity: "MEDIUM"
cvss: 6.0
epss: "31%"
vendor: "cure53"
kev: false
exploited: false
published: "2026-04-23 16:16:26"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-12T03:09:53+02:00"
---

# CVE-2026-41240

> 6.0 MEDIUM · 🧪 PoC

## Beschreibung

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Versions prior to 3.4.0 have an inconsistency between FORBID_TAGS and FORBID_ATTR handling when function-based ADD_TAGS is used. Commit c361baa added an early exit for FORBID_ATTR at line 1214. The same fix was not applied to FORBID_TAGS. At line 1118-1123, when EXTRA_ELEMENT_HANDLING.tagCheck returns true, the short-circuit evaluation skips the FORBID_TAGS check entirely. This allows forbidden elements to survive sanitization with their attributes intact. Version 3.4.0 patches the issue.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |

## Patch verfügbar (OSV)

- 5b16e0b892e82b1779d62b9928b43c4c4ff290b9 (Commit)
- c361baa18dbdcb3344a41110f4c48ad85bf48f80 (Commit)

## Referenzen

- <https://github.com/cure53/DOMPurify/security/advisories/GHSA-h7mw-gpvr-xq4m>
- <https://github.com/cure53/DOMPurify/commit/c361baa18dbdcb3344a41110f4c48ad85bf48f80>
- <https://github.com/cure53/DOMPurify/releases/tag/3.4.0>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-41240) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_