Cross-Site Scripting Vulnerability in DOMPurify by Cure53
CVE-2026-49978

6.3MEDIUM

Key Information:

Vendor

Cure53

Status
Dompurify
Vendor
CVE Published:
14 July 2026

What is CVE-2026-49978?

Previously, DOMPurify allowed an attacker to bypass sanitization through the IN_PLACE method due to its inability to properly handle shadow contents within .content elements. This oversight could enable the execution of malicious markup or scripts upon cloning and insertion of sanitized templates. The vulnerability has been addressed in version 3.4.7, improving the product's protection against XSS attacks.

Affected Version(s)

DOMPurify < 3.4.6

References

https://github.com/cure53/DOMPurify/security/advisories/G...
x_refsource_CONFIRM
https://github.com/cure53/DOMPurify/commit/ca30f070c360df...
x_refsource_MISC
https://github.com/cure53/DOMPurify/releases/tag/3.4.7
x_refsource_MISC

CVSS V4

Score:
6.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.