CVE-2026-54355
MediumCVSS 5.3Summary
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 without escaping it for a single-quoted JavaScript string. When the deployment trusts the forwarded header and does not configure a fixed ows_onlineresource or MS_ONLINERESOURCE value, embedded single quotes can escape the generated URL string. An unauthenticated attacker can craft a URL that executes arbitrary JavaScript in the MapServer site origin when opened by a victim. This issue is fixed in version 8.6.4.
Risk Assessment
An attacker can access the victim's sessions or tokens, same-origin data and requests, and perform actions as the victim. The risk occurs when the deployment trusts the X-Forwarded-Host header and lacks a fixed onlineresource configuration.
Recommendation
Update MapServer to version 8.6.4 or later. Configure a fixed ows_onlineresource or MS_ONLINERESOURCE value and do not trust the X-Forwarded-Host header from unknown sources.
Other vulnerabilities in MapServer
See all- CVE-2026-54354High
In MapServer prior to 8.6.4, PostGIS filter translation in msPostGISLayerTranslateFilter() treats a filteritem as numeric when CONNECTIONTYPE POSTGIS and Integer metadata are configured, but does not verify that attacker-controlled CGI or OGC API Features input is a numeric literal. The unquoted input is concatenated into the SQL predicate, enabling SQL injection.
- CVE-2016-9839High
In MapServer before version 7.0.3, OGR driver error messages are too verbose and may leak sensitive information if data connection fails.
- CVE-2017-5522Critical
A stack-based buffer overflow in MapServer before 6.0.6, 6.2.x before 6.2.4, 6.4.x before 6.4.5, and 7.0.x before 7.0.4 allows remote attackers to cause a denial of service (crash) or execute arbitrary code via vectors involving WFS get feature requests.
Original NVD description (English source)
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 HTTP_X_FORWARDED_HOST through msBuildOnlineResource(), processLine(), and the [mapserv_onlineresource] substitution in src/maputil.c and src/maptemplate.c without escaping it for a single-quoted JavaScript string. When the deployment trusts the forwarded header and does not configure a fixed ows_onlineresource or MS_ONLINERESOURCE value, embedded single quotes can escape the generated URL string. An unauthenticated attacker can craft a URL that executes arbitrary JavaScript in the MapServer site origin when opened by a victim, enabling access to sessions or tokens, same-origin data and requests, and actions as the victim. This issue is fixed in version 8.6.4.