CVE-2026-33721 (GCVE-0-2026-33721)

Vulnerability from cvelistv5 – Published: 2026-03-27 00:15 – Updated: 2026-04-17 17:18
VLAI
Title
MapServer has heap buffer overflow in SLD `Categorize` Threshold parsing
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-30 11:51 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
MapServer MapServer Affected: >= 4.2, < 8.6.1
guessed Create a notification for this product.
Show details on NVD website
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