6.9
MEDIUM CVSS 4.0
CVE-2026-83611
xmldom: Parser silently accepts a not-well-formed end tag whose name is followed by a line break and trailing content
Description

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. Prior to @xmldom/xmldom versions 0.8.15 and 0.9.12, and in xmldom version 0.6.0 and earlier, DOMParser.parseFromString() can silently accept an end tag such as </a\njunk>, close the element, and discard the trailing content. On 0.9.x, the lib/sax.js end-tag validator inherits the multiline flag from reg(), allowing the first line to satisfy the anchored XML ETag production; older lines have no equivalent residue validation. This parser differential can bypass a parse-before-trust well-formedness gate, although it does not inject the discarded content; onError on 0.9.x and errorHandler on 0.8.x are the relevant reporting interfaces. This issue is fixed in @xmldom/xmldom versions 0.8.15 and 0.9.12; no fixed version is available for xmldom.

INFO

Published Date :

Sept. 1, 2026, 3:17 p.m.

Last Modified :

Sept. 8, 2026, 9:11 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-83611 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.

ID Vendor Product Action
1 Xmldom_project xmldom
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 4.0 MEDIUM [email protected]
Solution
Update to a fixed version of the xmldom library to resolve parser issues.
  • Update @xmldom/xmldom to version 0.8.15 or 0.9.12.
  • Use newer versions of the xmldom library if available.
  • Apply relevant error handling and parsing logic.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-83611 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-2026-83611 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).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-83611 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-83611 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. Prior to @xmldom/xmldom versions 0.8.15 and 0.9.12, and in xmldom version 0.6.0 and earlier, DOMParser.parseFromString() can silently accept an end tag such as </a\njunk>, close the element, and discard the trailing content. On 0.9.x, the lib/sax.js end-tag validator inherits the multiline flag from reg(), allowing the first line to satisfy the anchored XML ETag production; older lines have no equivalent residue validation. This parser differential can bypass a parse-before-trust well-formedness gate, although it does not inject the discarded content; onError on 0.9.x and errorHandler on 0.8.x are the relevant reporting interfaces. This issue is fixed in @xmldom/xmldom versions 0.8.15 and 0.9.12; no fixed version is available for xmldom.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/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-1286
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/83xxx/CVE-2026-83611.json">CVE-2026-83611</a>
    Added Reference https://github.com/xmldom/xmldom/commit/4430189660b0d380ee9c9ee7550a1358688e8828
    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/pull/1072
    Added Reference https://github.com/xmldom/xmldom/releases/tag/0.8.15
    Added Reference https://github.com/xmldom/xmldom/releases/tag/0.9.12
    Added Reference https://github.com/xmldom/xmldom/security/advisories/GHSA-6h8r-xr42-gp59
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 01, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/xmldom/xmldom/security/advisories/GHSA-6h8r-xr42-gp59
    Added SSVC {'id': 'CVE-2026-83611', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-01T14:53:15.050065Z'}
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.