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.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.6",
  "pubDate": "2026-08-18T22:16:53.470Z",
  "pubdate": "2026-08-18T22:16:53.470Z",
  "executiveSummary": "A stored cross-site scripting vulnerability exists in the Maps MediaWiki extension prior to version 12.1.3.\nThe vulnerability resides within the display_map parser function utilizing the Leaflet service, specifically via the overlays parameter.\nAn authenticated wiki user with edit permissions can store malicious wikitext containing arbitrary JavaScript payloads.\nWhen another user previews or views the affected map, the payload executes within their browser session.\nSuccessful exploitation allows attackers to access sensitive session data or perform unauthorized actions on behalf of the victim.\nThe risk is mitigated by updating the Maps extension to version 12.1.3 or later, which addresses the lack of proper output escaping for layer-control labels.",
  "technicalDetails": "The vulnerability is caused by improper output handling and lack of sanitization within the Maps MediaWiki extension prior to version 12.1.3.\nSpecifically, the display_map parser function operating under the Leaflet service accepts attacker-controlled input via the overlays parameter.\nThe vulnerable component is identified as resources/leaflet/jquery.leaflet.js, which processes the overlay name and injects it directly into the Leaflet layer-control label without performing necessary HTML escaping.\nTo exploit this issue, an attacker requires wiki user privileges granting edit permissions, enabling them to store malicious wikitext on a vulnerable page.\nThe attack flow proceeds as follows: First, the attacker crafts a malicious wikitext payload incorporating arbitrary script content within the overlays parameter of a display_map function call. Second, the attacker saves or publishes the edited wiki page. Third, a victim user navigates to view or preview the affected map. Fourth, the MediaWiki extension renders the map, passing the unescaped overlay name to resources/leaflet/jquery.leaflet.js. Finally, the browser parses the unescaped input, resulting in the execution of the injected script in the context of the victim's browser session.\nThe payload executes with the privileges of the viewing user, allowing potential access to session tokens, cookies, or authorized wiki actions.\nThe issue is fully resolved in Maps version 12.1.3 by implementing proper escaping mechanisms for layer-control labels."
}