What is CVE-2026-116802?

CVE-2026-116802 is a medium-severity vulnerability in Cure53 Dompurify, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-10-27.

How severe is CVE-2026-116802?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Cure53 Dompurify

CVE-2026-116802

DOMPurify before 3.4.17 contains a cross-site scripting vulnerability that allows attackers to bypass the SMIL attributeName=href guard when PARSER_MEDIA_TYPE is application/xhtml+xml, because transformCaseFunc does not lowercase attribute names. Attackers can submit SVG with an animate or set element using attributeName="href" and a javascript: entry in values to execute script when users click the sanitized link.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-10-27.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Cure53 Dompurify

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/cure53/DOMPurify/security/advisories/GHSA-c6gr-qvv4-5v3f (vendor-advisory)
www.vulncheck.com/advisories/dompurify-before-3.4.17-xss-via-smil-attributename… (third-party-advisory)

Frequently asked questions

What is CVE-2026-116802?: CVE-2026-116802 is a medium-severity vulnerability in Cure53 Dompurify, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-10-27.
How severe is CVE-2026-116802?: Medium severity. CVSS v3 base score is 6.1 out of 10.