CVE-2026-49978

MEDIUM

DOMPurify IN_PLACE Sanitization Bypass via Attached Shadow Root Inside <template>.content

Title source: cna
STIX 2.1

Description

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.

References (3)

Core 3

Scores

CVSS v3 6.1
EPSS 0.0033
EPSS Percentile 26.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (2)
cure53/dompurify < 3.4.7
cure53/DOMPurify < 3.4.6
Published Jul 14, 2026
Tracked Since Jul 15, 2026