Description
MapServer is a system for developing web-based GIS applications. From version 6.0 to before version 8.6.2, a reflected XSS vulnerability in MapServer's WMS server allows an unauthenticated attacker to inject arbitrary HTML/JavaScript into the browser of any user who opens a crafted WMS URL. The vulnerability is triggered via FORMAT=application/openlayers combined with an unsanitized SRS parameter in WMS 1.3.0 requests. This issue has been patched in version 8.6.2.
Affected products
osgeo: mapserver
References3
- github.com/MapServer/MapServer/security/advisories/GHSA-4g9f-ph… ExploitVendor Advisory
- github.com/MapServer/MapServer/security/advisories/GHSA-4g9f-ph… ExploitVendor Advisory
- github.com/MapServer/MapServer/releases/tag/rel-8-6-2 ProductRelease Notes
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 16 · as of 13 November 2026
- CWE
- CWE-80
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