LanguageSelector Extension up to 1.38 on Mediawiki Downstream injection

Summaryinfo

A vulnerability classified as problematic was found in LanguageSelector Extension up to 1.38 on Mediawiki. This affects an unknown function of the component Downstream. Such manipulation leads to injection. This vulnerability is traded as CVE-2025-62697. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in LanguageSelector Extension up to 1.38 on Mediawiki. It has been rated as critical. Affected by this issue is an unknown function of the component Downstream. The manipulation with an unknown input leads to a injection vulnerability. Using CWE to declare the problem leads to CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') vulnerability in The Wikimedia Foundation Mediawiki - LanguageSelector Extension allows Code Injection.This issue affects Mediawiki - LanguageSelector Extension: from master before 1.39.

The weakness was shared by SomeRandomDeveloper. The advisory is shared for download at gerrit.wikimedia.org. This vulnerability is handled as CVE-2025-62697 since 10/20/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1055.

The vulnerability scanner Nessus provides a plugin with the ID 271642 (Linux Distros Unpatched Vulnerability : CVE-2025-62697), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.39 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (271642), EUVD (EUVD-2025-35095) and CERT Bund (WID-SEC-2025-2341). Once again VulDB remains the best source for vulnerability data.

Affected

• Open Source MediaWiki

Productinfo

Name

• LanguageSelector Extension

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 1.34
• 1.35
• 1.36
• 1.37
• 1.38

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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