CVE-2026-39933: CWE-79 Improper neutralization of input during web page generation ('cross-site scripting') in The Wikimedia Foundation Mediawiki - GlobalWatchlist Extension
CVE-2026-39933 is a cross-site scripting (XSS) vulnerability in the Wikimedia Foundation's Mediawiki GlobalWatchlist Extension. It arises from improper neutralization of input during web page generation. This vulnerability has been fixed in the master branch and in release branches for MediaWiki versions 1. 43, 1. 44, and 1. 45. The CVSS 4. 0 base score is 6. 9, indicating a medium severity level. No known exploits are reported in the wild.
AI Analysis
Technical Summary
The vulnerability CVE-2026-39933 is a CWE-79 cross-site scripting flaw in the GlobalWatchlist Extension of MediaWiki maintained by the Wikimedia Foundation. It results from improper input neutralization during web page generation, enabling potential injection of malicious scripts. The issue has been addressed and remediated in the master branch and release branches for MediaWiki versions 1.43, 1.44, and 1.45. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges or user interaction required, and low to low-medium impact on confidentiality, integrity, availability, scope, and security requirements. There is no indication of known active exploitation. The vendor has not explicitly stated the remediation level, but the fix is available in the specified branches.
Potential Impact
Successful exploitation could allow an attacker to execute arbitrary scripts in the context of the affected web application, potentially leading to unauthorized actions or data exposure within the scope of the MediaWiki GlobalWatchlist Extension. The impact is rated medium with a CVSS score of 6.9. No known exploits are currently reported in the wild.
Mitigation Recommendations
A fix has been implemented and is available in the master branch and release branches for MediaWiki versions 1.43, 1.44, and 1.45. Users of the GlobalWatchlist Extension should upgrade to one of these patched versions to remediate the vulnerability. Patch status is confirmed by the vendor advisory information. No additional mitigation steps are indicated.
CVE-2026-39933: CWE-79 Improper neutralization of input during web page generation ('cross-site scripting') in The Wikimedia Foundation Mediawiki - GlobalWatchlist Extension
Description
CVE-2026-39933 is a cross-site scripting (XSS) vulnerability in the Wikimedia Foundation's Mediawiki GlobalWatchlist Extension. It arises from improper neutralization of input during web page generation. This vulnerability has been fixed in the master branch and in release branches for MediaWiki versions 1. 43, 1. 44, and 1. 45. The CVSS 4. 0 base score is 6. 9, indicating a medium severity level. No known exploits are reported in the wild.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-39933 is a CWE-79 cross-site scripting flaw in the GlobalWatchlist Extension of MediaWiki maintained by the Wikimedia Foundation. It results from improper input neutralization during web page generation, enabling potential injection of malicious scripts. The issue has been addressed and remediated in the master branch and release branches for MediaWiki versions 1.43, 1.44, and 1.45. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges or user interaction required, and low to low-medium impact on confidentiality, integrity, availability, scope, and security requirements. There is no indication of known active exploitation. The vendor has not explicitly stated the remediation level, but the fix is available in the specified branches.
Potential Impact
Successful exploitation could allow an attacker to execute arbitrary scripts in the context of the affected web application, potentially leading to unauthorized actions or data exposure within the scope of the MediaWiki GlobalWatchlist Extension. The impact is rated medium with a CVSS score of 6.9. No known exploits are currently reported in the wild.
Mitigation Recommendations
A fix has been implemented and is available in the master branch and release branches for MediaWiki versions 1.43, 1.44, and 1.45. Users of the GlobalWatchlist Extension should upgrade to one of these patched versions to remediate the vulnerability. Patch status is confirmed by the vendor advisory information. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- wikimedia-foundation
- Date Reserved
- 2026-04-07T21:25:36.589Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d5826f43e2781bad7a17c8
Added to database: 4/7/2026, 10:17:19 PM
Last enriched: 4/15/2026, 12:35:47 PM
Last updated: 5/25/2026, 5:59:40 AM
Views: 98
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