CVE-2026-83612

Name	CVE-2026-83612
Description	xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.0-beta.1 until 0.9.12, HTML-mode parsing through DOMParser.parseFromString() mishandles a mixed-case closing tag for the script, style, textarea, or title raw-text elements. parseHtmlSpecialContent, selected by isHTMLRawTextElement or isHTMLEscapableRawTextElement, uses a case-sensitive indexOf() and then calls substring() with a missing-close result of negative one, causing unstable parser progression and quadratic output amplification. A small untrusted text/html document can consequently consume disproportionate CPU and memory when parsed and serialized. This issue is fixed in @xmldom/xmldom version 0.9.12.
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-xmldom (PTS)	bookworm	0.8.6-1	vulnerable
	trixie	0.9.6-1	vulnerable
	forky, sid	0.9.11-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
node-xmldom	source	(unstable)	(unfixed)

Notes

https://github.com/xmldom/xmldom/security/advisories/GHSA-6mj3-qw4j-hgrw
https://github.com/xmldom/xmldom/pull/1071
Fixed by: https://github.com/xmldom/xmldom/commit/7ced40c06c28d151e996a97045018c3559ae4707 (0.9.12)