CVE-2026-49978

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.7, DOMPurify IN_PLACE sanitization could skip shadow contents attached to an element inside <template>.content, allowing attacker-controlled markup such as event handlers, JavaScript URLs, or scripts to survive and execute when an application cloned and inserted the sanitized template. This issue is fixed in version 3.4.7.

CVSS 4.0

6.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N

CVSS 3.1

6.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS

0.4% chance of exploitation in the next 30 days; higher than 34% of CVEs (scores of 2026-10-25)

CWE

CWE-79

Published

2026-07-14

Modified

2026-10-24

Record from

the NVD, synced 2026-10-25

Affected

• cure53:dompurify

Packages (OSV)

References

• https://github.com/cure53/DOMPurify/commit/ca30f070c360df162a3e3848e80e6fd3c9e74bff
• https://github.com/cure53/DOMPurify/releases/tag/3.4.7
• https://github.com/cure53/DOMPurify/security/advisories/GHSA-rp9w-3fw7-7cwq
• https://github.com/cure53/DOMPurify/security/advisories/GHSA-rp9w-3fw7-7cwq

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