CVE-2026-45104

HIGH EPSS 23.8%
Published May 27, 20261mo ago · Modified Jun 17, 20261w ago
7.5 CVSS 3.1
High
Find Similar
Published May 27, 2026 1mo ago
Last Modified Jun 17, 2026 1w ago

Description

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 <Rule> carrying <ElseFilter/> — 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.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
23.8% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 2

CWE-129
CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 1

VendorProductVersionRange
osgeomapserver*≥6.4.0  –  <8.6.3

References 1

  • github.com https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m
    ExploitMitigationVendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.