Vulnerability record · CVE-2026-42030 · published 8 May 2026
CVE-2026-42030: Osgeo mapserver vulnerability
Osgeo · Mapserver
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.
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://github.com/MapServer/MapServer/releases/tag/rel-8-6-2 | ProductRelease Notes |
| https://github.com/MapServer/MapServer/security/advisories/GHSA-4g9f-ph64-hg2x | ExploitVendor Advisory |
| https://github.com/MapServer/MapServer/security/advisories/GHSA-4g9f-ph64-hg2x | ExploitVendor Advisory |
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-42030), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.