Medium severity5.3NVD Advisory· Published Mar 27, 2026· Updated Apr 17, 2026
CVE-2026-33721
CVE-2026-33721
Description
MapServer is a system for developing web-based GIS applications. Starting in version 4.2 and prior to version 8.6.1, a heap-buffer-overflow write in MapServer’s SLD (Styled Layer Descriptor) parser lets a remote, unauthenticated attacker crash the MapServer process by sending a crafted SLD with more than 100 Threshold elements inside a ColorMap/Categorize structure (commonly reachable via WMS GetMap with SLD_BODY). Version 8.6.1 patches the issue.
Affected products
1Patches
0No patches discovered yet.
Vulnerability mechanics
AI mechanics synthesis has not run for this CVE yet.
References
3- github.com/MapServer/MapServer/security/advisories/GHSA-cv4m-mr84-fgjpnvdExploitMitigationVendor Advisory
- github.com/MapServer/MapServer/releases/tag/rel-8-6-1nvdProductRelease Notes
- lists.debian.org/debian-lts-announce/2026/04/msg00017.htmlnvd
News mentions
0No linked articles in our index yet.