---
id: CVE-2026-83609
title: >-
  xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core)
  DOMParser and XMLSerializer module
summary: >-
  xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core)
  DOMParser and XMLSerializer module. From 0.9.0 until 0.9.12, the shared reg()
  builder in lib/grammar.js compiles the anchored QName_exact validator with the
  multiline …
severity: high
cwe:
  - CWE-91
  - CWE-625
vendor: xmldom
product: '@xmldom/xmldom'
affected:
  - '@xmldom/xmldom >= 0.9.0, <= 0.9.11'
patched:
  - '@xmldom/xmldom 0.9.12'
published: '2026-09-01'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T21:11:31.703'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-83609'
references:
  - url: >-
      https://github.com/xmldom/xmldom/commit/7b2ec67e1750daadd0bb06c92e875e726544a362
    label: security-advisories@github.com
  - url: 'https://github.com/xmldom/xmldom/pull/1071'
    label: security-advisories@github.com
  - url: 'https://github.com/xmldom/xmldom/releases/tag/0.9.12'
    label: security-advisories@github.com
  - url: 'https://github.com/xmldom/xmldom/security/advisories/GHSA-3px3-54cx-rmw9'
    label: security-advisories@github.com
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-83609'
  - url: 'https://github.com/advisories/GHSA-3px3-54cx-rmw9'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-83609.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-83609'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2526815'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-83609'
tags:
  - nvd
  - ghsa
  - npm
  - csaf
  - vex
  - red-hat
aliases:
  - GHSA-3px3-54cx-rmw9
ecosystem: npm
epss: 0.00543
epssPercentile: 0.43141
ingestedAt: '2026-09-08T21:11:12.320Z'
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'
cvssSource: vendor
---

## Overview

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.0 until 0.9.12, the shared reg() builder in lib/grammar.js compiles the anchored QName_exact validator with the multiline flag, so ^ and $ validate only one line instead of the complete name. createElementNS, createAttributeNS, createDocumentType, and createAttribute consequently accept a malformed XML name whose first line is valid and whose later text injects markup when serialized through either the default path or requireWellFormed: true. The triggering ECMAScript line terminators are U+000A, U+000D, U+2028, and U+2029. This issue is fixed in @xmldom/xmldom version 0.9.12.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-83609)

Affected packages:

- `@xmldom/xmldom >= 0.9.0, <= 0.9.11`

Patched in:

- `@xmldom/xmldom 0.9.12`

Source: https://github.com/advisories/GHSA-3px3-54cx-rmw9

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat Build of Podman Desktop, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat Fuse 7, Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat Fuse 7, Red Hat Build of Podman Desktop, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, … · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-83609.json)