CVE-2026-54355 MapServer: Reflected XSS in OpenLayers HTML Output via `HTTP_X_FORWARDED_HOST`

MapServer is a system for developing web-based GIS applications. From 6.0 until 8.6.4, MapServer's OpenLayers HTML output for SERVICE=WMS&REQUEST=GetMap&FORMAT=application/openlayers reflects an attacker-controlled X-Forwarded-Host value received as HTTPXFORWARDEDHOST through msBuildOnlineResourc...