CVE-2026-66010

Name	CVE-2026-66010
Description	DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
node-dompurify (PTS)	bookworm	2.4.1+dfsg+~2.4.0-2+deb12u1	vulnerable
	bookworm (security)	2.4.1+dfsg+~2.4.0-2	vulnerable
	trixie	3.1.7+dfsg+~3.0.5-2	vulnerable
	forky, sid	3.4.12+dfsg-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
node-dompurify	source	(unstable)	3.4.12+dfsg-1

https://github.com/cure53/DOMPurify/security/advisories/GHSA-c2j3-45gr-mqc4