cve.bz

CVE-2026-45104

7.5 highEPSS 0.3%

High (7.5) in osgeo mapserver. EPSS 0.3% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.3% chance of exploitation in the next 30 days; higher than 25% of CVEs (scores of 2026-10-31)
CWEs
CWE-476, CWE-129
Published
Modified
Record from
the NVD, synced

Affected

References

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