GHSA-4h7g-5542-v3fc: mediawiki/maps has stored XSS through the overlays parameter in the display_map parser function
A stored cross-site scripting (XSS) vulnerability exists in the mediawiki/maps extension through the overlays parameter of the display_map parser function when using the leaflet service. The vulnerability arises because overlay names are not properly escaped before being passed to leaflet, which inserts them as HTML. This allows any user with edit permissions to inject malicious HTML or JavaScript code that is stored and executed when the map is viewed.
AI Analysis
Technical Summary
The mediawiki/maps extension prior to version 12.1.3 contains a stored XSS vulnerability (CVE-2026-52854) in the display_map parser function's overlays parameter when used with the leaflet service. Overlay names are not escaped before being passed to leaflet.js, which inserts them directly as HTML, enabling stored XSS attacks. An attacker with edit permissions can inject malicious HTML/JavaScript via the overlays parameter in wikitext, which will execute in the context of users viewing the map. This vulnerability is tracked as CWE-79 and CWE-80 and has a high severity rating.
Potential Impact
Successful exploitation allows an attacker with edit permissions to perform stored XSS attacks, potentially leading to arbitrary script execution in the browsers of users viewing the affected maps. This can result in session hijacking, defacement, or other malicious actions. The vulnerability affects confidentiality, integrity, and availability as indicated by the CVSS vector (C:H/I:L/A:L).
Mitigation Recommendations
A fix is available in mediawiki/maps version 12.1.3 and later. Users should upgrade to version 12.1.3 or newer to remediate this vulnerability. Until upgraded, restrict edit permissions to trusted users only to reduce risk. Patch status is confirmed by the affectedVersions data indicating versions prior to 12.1.3 are vulnerable.
GHSA-4h7g-5542-v3fc: mediawiki/maps has stored XSS through the overlays parameter in the display_map parser function
Description
A stored cross-site scripting (XSS) vulnerability exists in the mediawiki/maps extension through the overlays parameter of the display_map parser function when using the leaflet service. The vulnerability arises because overlay names are not properly escaped before being passed to leaflet, which inserts them as HTML. This allows any user with edit permissions to inject malicious HTML or JavaScript code that is stored and executed when the map is viewed.
CVSS v3.1
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The mediawiki/maps extension prior to version 12.1.3 contains a stored XSS vulnerability (CVE-2026-52854) in the display_map parser function's overlays parameter when used with the leaflet service. Overlay names are not escaped before being passed to leaflet.js, which inserts them directly as HTML, enabling stored XSS attacks. An attacker with edit permissions can inject malicious HTML/JavaScript via the overlays parameter in wikitext, which will execute in the context of users viewing the map. This vulnerability is tracked as CWE-79 and CWE-80 and has a high severity rating.
Potential Impact
Successful exploitation allows an attacker with edit permissions to perform stored XSS attacks, potentially leading to arbitrary script execution in the browsers of users viewing the affected maps. This can result in session hijacking, defacement, or other malicious actions. The vulnerability affects confidentiality, integrity, and availability as indicated by the CVSS vector (C:H/I:L/A:L).
Mitigation Recommendations
A fix is available in mediawiki/maps version 12.1.3 and later. Users should upgrade to version 12.1.3 or newer to remediate this vulnerability. Until upgraded, restrict edit permissions to trusted users only to reduce risk. Patch status is confirmed by the affectedVersions data indicating versions prior to 12.1.3 are vulnerable.
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: 07/02/2026, 23:16:58 UTC
Last updated: 07/02/2026, 23:16:58 UTC
Views: 2
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