Cross-Site Scripting Vulnerability in DOMPurify Affects Web Security
CVE-2026-116802

5.1MEDIUM

Key Information:

Vendor

Cure53

Status
Dompurify
Vendor
CVE Published:
26 October 2026

What is CVE-2026-116802?

A cross-site scripting vulnerability exists in DOMPurify versions prior to 3.4.17, allowing attackers to bypass security guards related to the SMIL attributeName when using application/xhtml+xml as the media type. This specific issue arises because the transformCaseFunc function fails to convert attribute names to lowercase. As a result, attackers can submit SVG content that includes animate or set elements with attributeName set to 'href' containing 'javascript:' entries. When users click these sanitized links, malicious scripts may be executed, posing serious security risks.

Affected Version(s)

DOMPurify 0 < 3.4.17

DOMPurify 3.4.17

References

https://github.com/cure53/DOMPurify/security/advisories/G...
vendor-advisory
https://www.vulncheck.com/advisories/dompurify-before-3.4...
third-party-advisory

CVSS V4

Score:
5.1
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

Credit

Koukyosyumei
.