Wikimedia MediaWiki up to 1.43.6/1.44.3/1.45.1 ActionEntryPoint.Php cross site scripting

Summaryinfo

A vulnerability classified as problematic has been found in Wikimedia MediaWiki up to 1.43.6/1.44.3/1.45.1. Affected is an unknown function of the file includes/Actions/ActionEntryPoint.Php. The manipulation leads to cross site scripting. This vulnerability is traded as CVE-2026-34095. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Wikimedia MediaWiki up to 1.43.6/1.44.3/1.45.1 and classified as problematic. This issue affects some unknown processing of the file includes/Actions/ActionEntryPoint.Php. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-80. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages. Impacted is integrity. The summary by CVE is:

Vulnerability in Wikimedia Foundation MediaWiki. This vulnerability is associated with program files includes/Actions/ActionEntryPoint.Php, includes/Request/FauxResponse.Php. This issue affects MediaWiki: from * before 1.43.7, 1.44.4, 1.45.2.

The advisory is shared at phabricator.wikimedia.org. The identification of this vulnerability is CVE-2026-34095 since 03/25/2026. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

By approaching the search of inurl:includes/Actions/ActionEntryPoint.Php it is possible to find vulnerable targets with Google Hacking. The vulnerability scanner Nessus provides a plugin with the ID 321929 (Debian dla-4640 : mediawiki - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.43.7, 1.44.4 or 1.45.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (321929). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Content Management System

Vendor

• Wikimedia

Name

• MediaWiki

Version

• 1.43.0
• 1.43.1
• 1.43.2
• 1.43.3
• 1.43.4
• 1.43.5
• 1.43.6
• 1.44.0
• 1.44.1
• 1.44.2
• 1.44.3
• 1.45.0
• 1.45.1

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

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• 🔒
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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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