dbcve.org
InjectionWeakness · CWE-74

CVE-2025-62697

HIGH · 8.8 CVSS v4.0 Published 2025-10-20
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
97/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

This is an injection vulnerability in the MediaWiki LanguageSelector extension. The vulnerability stems from improper neutralization of special elements in output, allowing an attacker to inject malicious code. Given the CVSS of 8.8 and description mentioning Code Injection, this is likely a cross-site scripting (XSS) or similar injection flaw where language/locale parameters are not properly sanitized before being rendered.

MitigationUpdate the LanguageSelector extension to version 1.39 or later. If immediate patching is not feasible, consider disabling the extension or implementing input validation at the web server level as a temporary workaround.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:L/SI:L/SA:L/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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify LanguageSelector extension is installed
    Check for the LanguageSelector extension directory in your MediaWiki extensions folder. Look for a folder named LanguageSelector or similar in the extensions/ directory.
    Affected if The LanguageSelector extension directory exists in your MediaWiki installation.
  2. Determine the installed LanguageSelector version
    Open the extension's version file (such as extension.json, composer.json, or a version.php file within the LanguageSelector extension directory) and locate the version number.
    Affected if The installed version is lower than 1.39 (for example, 1.38.x, 1.37.x, or earlier).
  3. Confirm the extension is enabled in MediaWiki configuration
    Check your MediaWiki configuration file (usually LocalSettings.php) for a line that enables the extension, such as wfLoadExtension( 'LanguageSelector' ) or similar.
    Affected if The extension is enabled in the configuration.
  4. Verify the language selector feature is accessible
    Check if the language selection functionality is rendered on your wiki. Visit pages where language selection UI typically appears (often in user preferences or site footer) and inspect whether the language selector dropdown or input is present and functional.
    Affected if The language selector UI is displayed to users on your wiki.

You are affected if the LanguageSelector extension is installed, enabled, version is below 1.39, and the language selection feature is accessible to users.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update the LanguageSelector extension to version 1.39 or later. If immediate patching is not feasible, consider disabling the extension or implementing input validation at the web server level as a temporary workaround.

Recommended fix Moderate confidence

LanguageSelector extension version 1.39 or later

  1. Identify the current version of the MediaWiki LanguageSelector extension by checking the extension's version file or composer.json
  2. Back up the MediaWiki installation and database before making changes
  3. Upgrade the LanguageSelector extension to version 1.39 or later by running: composer update wikimedia/language-selector or pulling the latest version from the extension repository
  4. Clear any caching mechanisms (e.g., PHP opcache, MediaWiki object cache) after the upgrade
  5. Verify the extension is loaded correctly by accessing a wiki page and checking for proper functionality
  6. Test that the language selector functionality works as expected and no injection vulnerabilities are present

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-62697 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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