xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.11 until 0.9.12, the requireWellFormed: true element and attribute name checks use the anchored QName_exact expression produced by reg() in lib/grammar.js, which inherits the multiline flag. A name with a valid first line followed by U+000A, U+000D, U+2028, or U+2029 and breakout markup therefore passes validation and is emitted verbatim in element start and end tags or attribute names. This bypasses the strict-serialization checks introduced for the earlier element-name and attribute-name injection advisories, while the default serialization path remains outside the strict guarantee. This issue is fixed in @xmldom/xmldom version 0.9.12.
History

Tue, 01 Sep 2026 22:00:00 +0000

Type Values Removed Values Added
First Time appeared Xmldom
Xmldom xmldom
Vendors & Products Xmldom
Xmldom xmldom
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 01 Sep 2026 15:00:00 +0000

Type Values Removed Values Added
Description xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.11 until 0.9.12, the requireWellFormed: true element and attribute name checks use the anchored QName_exact expression produced by reg() in lib/grammar.js, which inherits the multiline flag. A name with a valid first line followed by U+000A, U+000D, U+2028, or U+2029 and breakout markup therefore passes validation and is emitted verbatim in element start and end tags or attribute names. This bypasses the strict-serialization checks introduced for the earlier element-name and attribute-name injection advisories, while the default serialization path remains outside the strict guarantee. This issue is fixed in @xmldom/xmldom version 0.9.12.
Title xmldom: requireWellFormed element/attribute name validation is bypassable via an embedded line terminator
Weaknesses CWE-625
CWE-91
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-09-01T14:47:46.526Z

Updated: 2026-09-01T15:30:45.725Z

Reserved: 2026-08-31T20:36:25.744Z

Link: CVE-2026-83617

cve-icon Vulnrichment

Updated: 2026-09-01T15:30:42.162Z

cve-icon NVD

Status : Deferred

Published: 2026-09-01T15:17:40.273

Modified: 2026-09-08T21:11:31.703

Link: CVE-2026-83617

cve-icon Redhat

No data.