CVE-2026-45104

published 2026-05-27

CVE-2026-45104: MapServer is a system for developing web-based GIS applications. From 6.4.0 to before 8.6.3, msSLDParseUserStyle always calls _SLDApplyRuleValues(psRule…

Priority P3 40 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

MapServer is a system for developing web-based GIS applications. From 6.4.0 to before 8.6.3, msSLDParseUserStyle always calls _SLDApplyRuleValues(psRule, psLayer, 1); for any carrying — it assumes msSLDParseRule added one class. When the rule has no symbolizer (a structurally valid SLD), msSLDParseRule adds zero, and _SLDApplyRuleValues ends up indexing _class[-1], resulting in a NULL pointer dereference. A 200-byte well-formed SLD via the WMS SLD_BODY= parameter is enough to trigger this, no auth required. This vulnerability is fixed in 8.6.3.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
mapserver	mapserver	—	—
osgeo	mapserver	>= 6.4.0 < 8.6.3	8.6.3

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CWE-129 CWE-476