CVE-2026-83609
xmldom: Creation-time XML Name/QName validation is bypassable via an embedded line terminator, allowing injection on the default serialization path
Description
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.
INFO
Published Date :
Sept. 1, 2026, 3:17 p.m.
Last Modified :
Sept. 1, 2026, 3:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-83609
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update the xmldom library to version 0.9.12 or later.
- Validate XML names for proper structure.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-83609.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-83609 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-83609
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-83609 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-83609 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Sep. 01, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-91 Added CWE CWE-625 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/83xxx/CVE-2026-83609.json">CVE-2026-83609</a> Added Reference https://github.com/xmldom/xmldom/commit/7b2ec67e1750daadd0bb06c92e875e726544a362 Added Reference https://github.com/xmldom/xmldom/pull/1071 Added Reference https://github.com/xmldom/xmldom/releases/tag/0.9.12 Added Reference https://github.com/xmldom/xmldom/security/advisories/GHSA-3px3-54cx-rmw9