4.8
MEDIUM CVSS 4.0
CVE-2026-100383
Stored i18n XSS in WikiLambda's VisualEditor integration
Description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki - WikiLambda Extension allows Cross-Site Scripting (XSS). This issue affects Mediawiki - WikiLambda Extension: 1.47.0-alpha. The issue has been remediated on the `master` branch.

INFO

Published Date :

Sept. 25, 2026, 10:17 p.m.

Last Modified :

Sept. 25, 2026, 10:17 p.m.

Remotely Exploit :

Yes !

Source :

c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
Affected Products

The following products are affected by CVE-2026-100383 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
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 4.0 MEDIUM c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
CVSS 4.0 MEDIUM c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
Solution
Update Mediawiki WikiLambda Extension to a version that includes the fix for XSS.
  • Update Mediawiki WikiLambda Extension to a patched version.
  • Apply the patch from the master branch.
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-2026-100383.

URL Resource
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/WikiLambda/+/1326391
https://phabricator.wikimedia.org/T434967
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-100383 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-2026-100383 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-2026-100383 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-100383 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 c4f26cc8-17ff-4c99-b5e2-38fc1793eacc

    Sep. 25, 2026

    Action Type Old Value New Value
    Added Description Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki - WikiLambda Extension allows Cross-Site Scripting (XSS). This issue affects Mediawiki - WikiLambda Extension: 1.47.0-alpha. The issue has been remediated on the `master` branch.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:N/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-79
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/100xxx/CVE-2026-100383.json">CVE-2026-100383</a>
    Added Reference https://gerrit.wikimedia.org/r/c/mediawiki/extensions/WikiLambda/+/1326391
    Added Reference https://phabricator.wikimedia.org/T434967
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.