Maps is a MediaWiki extension that enables visualization of geographic data through dynamic embedded maps. (CVE-2026-52854)
Maps is a MediaWiki extension that enables visualization of geographic data through dynamic embedded maps. Prior to version 12.1.3, the display_map parser function in the Leaflet service accepts attacker-controlled HTML in the overlays parameter, and resources/leaflet/jquery.leaflet.js uses the overlay name as a Leaflet layer-control label without escaping it. A wiki user with the edit permission can store malicious wikitext that causes script execution when another user previews or views the affected map. The script executes in the viewing user's browser session and can access data or perform actions available to that user. This issue is fixed in version 12.1.3.
AI Analysis
Technical Summary
The mediawiki/maps extension contains a stored XSS vulnerability (CVE-2026-52854) due to failure to escape overlay names before passing them to the leaflet JavaScript library. Leaflet inserts these overlay names as HTML without sanitization, enabling stored XSS via the overlays parameter of the display_map parser function. This can be exploited by any user with edit permissions by injecting malicious HTML payloads into wikitext overlays, which are then rendered and executed in users' browsers.
Potential Impact
Successful exploitation allows an attacker with edit permissions to inject and execute arbitrary JavaScript code in the context of the MediaWiki site. This can lead to session hijacking, defacement, or other malicious actions affecting users who view the injected content. The vulnerability has a high severity score (CVSS 8.6) reflecting its network attack vector, low complexity, no user interaction, and high confidentiality impact.
Mitigation Recommendations
An official patch is available that fixes this vulnerability. Users should upgrade mediawiki/maps to version 12.1.3 or later to remediate this issue. Until patched, restrict edit permissions to trusted users to reduce the risk of exploitation.
Maps is a MediaWiki extension that enables visualization of geographic data through dynamic embedded maps. (CVE-2026-52854)
Description
Maps is a MediaWiki extension that enables visualization of geographic data through dynamic embedded maps. Prior to version 12.1.3, the display_map parser function in the Leaflet service accepts attacker-controlled HTML in the overlays parameter, and resources/leaflet/jquery.leaflet.js uses the overlay name as a Leaflet layer-control label without escaping it. A wiki user with the edit permission can store malicious wikitext that causes script execution when another user previews or views the affected map. The script executes in the viewing user's browser session and can access data or perform actions available to that user. This issue is fixed in version 12.1.3.
CVSS v3.1
Score 8.6high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The mediawiki/maps extension contains a stored XSS vulnerability (CVE-2026-52854) due to failure to escape overlay names before passing them to the leaflet JavaScript library. Leaflet inserts these overlay names as HTML without sanitization, enabling stored XSS via the overlays parameter of the display_map parser function. This can be exploited by any user with edit permissions by injecting malicious HTML payloads into wikitext overlays, which are then rendered and executed in users' browsers.
Potential Impact
Successful exploitation allows an attacker with edit permissions to inject and execute arbitrary JavaScript code in the context of the MediaWiki site. This can lead to session hijacking, defacement, or other malicious actions affecting users who view the injected content. The vulnerability has a high severity score (CVSS 8.6) reflecting its network attack vector, low complexity, no user interaction, and high confidentiality impact.
Mitigation Recommendations
An official patch is available that fixes this vulnerability. Users should upgrade mediawiki/maps to version 12.1.3 or later to remediate this issue. Until patched, restrict edit permissions to trusted users to reduce the risk of exploitation.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-4h7g-5542-v3fc
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-52854"]
- Ecosystems
- ["Packagist"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a46ecc327e9c7971943d5cc
Added to database: 07/02/2026, 22:57:07 UTC
Last enriched: 08/19/2026, 11:10:29 UTC
Last updated: 09/12/2026, 10:01:31 UTC
Views: 114
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