CVE-2026-42030
MapServer: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) in OpenLayers viewer
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
MapServer: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) in OpenLayers viewer
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.
- Record
CVE-2026-42030- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-80
- Updated
- 2026-11-02
EUVDEUVD-2026-28807
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.
- Record
EUVD-2026-28807- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-42030- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-80
- Updated
- 2026-11-11
OSV
MapServer: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) in OpenLayers viewer
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.
- Record
CVE-2026-42030- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-80
- Updated
- 2026-11-13
OSVDEBIAN-CVE-2026-42030
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.
- Record
DEBIAN-CVE-2026-42030- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-12
OSVUBUNTU-CVE-2026-42030
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.
- Record
UBUNTU-CVE-2026-42030- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mapserverDebian:12 | All versions, plus listed versions 8.0.0-38.0.0-3+deb12u18.0.1-18.0.1-1~exp18.0.1-2 Show 45 moreShow less8.0.1-2.1~exp18.0.1-2~bpo12+18.0.1-38.0.1-3~exp18.0.1-48.0.1-58.0.2-18.0.2-1~bpo12+18.2.0-18.2.0-1~bpo12+18.2.0~beta1-1~exp18.2.0~beta2-1~exp18.2.0~beta3-1~exp18.2.0~rc1-1~exp18.2.0~rc2-1~exp18.2.0~rc3-1~exp18.2.1-18.2.1-1~bpo12+18.2.2-18.2.2-1~bpo12+18.4.0-18.4.0-1~bpo12+18.4.0-28.4.0-38.4.0-48.4.0~beta1-1~exp18.4.0~beta2-1~exp18.4.0~rc1-1~exp18.4.1-18.4.1-1~bpo13+18.4.1-28.6.0-18.6.0-1~bpo13+18.6.0~beta1-1~exp18.6.0~beta2-1~exp18.6.0~rc1-1~exp18.6.1-18.6.1-1~bpo13+18.6.2-18.6.2-1~bpo13+18.6.3-18.6.3-1~bpo13+18.6.4-18.6.4-1~bpo13+18.6.5-1 | None known |
mapserverDebian:13 | All versions, plus listed versions 8.4.0-48.4.0-4+deb13u18.4.0-4+deb13u28.4.1-18.4.1-1~bpo13+1 Show 18 moreShow less8.4.1-28.6.0-18.6.0-1~bpo13+18.6.0~beta1-1~exp18.6.0~beta2-1~exp18.6.0~rc1-1~exp18.6.1-18.6.1-1~bpo13+18.6.2-18.6.2-1~bpo13+18.6.3-18.6.3-1~bpo13+18.6.4-18.6.4-1~bpo13+18.6.5-18.6.5-1~bpo13+18.6.6-18.6.6-1~bpo13+1 | None known |
mapserverDebian:14 | before 8.6.2-1, plus listed versions 8.4.0-48.4.1-18.4.1-1~bpo13+18.4.1-28.6.0-1 Show 7 moreShow less8.6.0-1~bpo13+18.6.0~beta1-1~exp18.6.0~beta2-1~exp18.6.0~rc1-1~exp18.6.1-18.6.1-1~bpo13+18.6.2-1~bpo13+1 | 8.6.2-1 |
mapserverUbuntu:16.04:LTS | All versions, plus listed versions 7.0.0-4build17.0.0-5ubuntu17.0.0-77.0.0-87.0.0-8build1 Show 5 moreShow less7.0.0-97.0.0-9ubuntu17.0.0-9ubuntu27.0.0-9ubuntu37.0.0-9ubuntu3.1 | None known |
mapserverUbuntu:18.04:LTS | All versions, plus listed versions 7.0.6-2build17.0.7-17.0.7-1build17.0.7-1build2 | None known |
mapserverUbuntu:20.04:LTS | All versions, plus listed versions 7.4.1-1build17.4.1-1build37.4.2-17.4.2-1build17.4.3-17.4.3-1build27.4.3-27.4.3-2build1 | None known |
mapserverUbuntu:22.04:LTS | All versions, plus listed versions 7.6.3-1~exp1ubuntu17.6.4-27.6.4-2build2 | None known |
mapserverUbuntu:24.04:LTS | All versions, plus listed versions 8.0.1-2build18.0.1-2build28.0.1-2build38.0.1-2build58.0.1-4ubuntu18.0.1-4ubuntu2 | None known |
mapserverUbuntu:25.10 | All versions, plus listed versions 8.4.0-1build18.4.0-48.4.0-4build1 | None known |
mapserverUbuntu:26.10 | All versions, plus listed versions 8.6.0-1build18.6.4-18.6.5-18.6.5-1build1 | None known |
mapserverUbuntu:26.04:LTS | All versions, plus listed versions 8.4.0-4build18.4.1-18.4.1-1build18.4.1-28.4.1-2build18.6.0-18.6.0-1build1 | None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | NVD | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-42030 is a medium vulnerability (CVSS 6.1) in Mapserver, published May 8, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.25%, the 16th percentile. Fixed in mapserver 8.6.2-1.
References
github.com/MapServer/MapServer/security/advisories/GHSA-4g9f-ph64-hg2x
nvd.nist.gov/vuln/detail/CVE-2026-42030
security-tracker.debian.org/tracker/CVE-2026-42030
ubuntu.com/security/CVE-2026-42030
cve.org/CVERecord?id=CVE-2026-42030
Left out here: 3 versions. The JSON record has them.