{"id":"CVE-2026-45104","state":"PUBLISHED","title":"MapServer: NULL pointer dereference in SLD `<ElseFilter>` rule parsing reachable via WMS `SLD_BODY`","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.","publishedAt":"2026-05-27T18:41:39.396Z","updatedAt":"2026-06-01T17:08:18.608Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["MapServer MapServer"],"affected":[{"vendor":"MapServer","product":"MapServer","versions":[{"version":">= 6.4.0, < 8.6.3","status":"affected"}]}],"references":["https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m"],"weaknesses":["CWE-129","CWE-476"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/45xxx/CVE-2026-45104.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45104","state":"PUBLISHED","datePublished":"2026-05-27T18:41:39.396Z","dateUpdated":"2026-06-01T17:08:18.608Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-08T19:27:26.699Z"},"containers":{"cna":{"title":"MapServer: NULL pointer dereference in SLD `<ElseFilter>` rule parsing reachable via WMS `SLD_BODY`","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"MapServer","product":"MapServer","versions":[{"version":">= 6.4.0, < 8.6.3","status":"affected"}]}],"references":[{"url":"https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m","name":"https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-129","lang":"en","description":"CWE-129: Improper Validation of Array Index","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-476","lang":"en","description":"CWE-476: NULL Pointer Dereference","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-27T18:41:39.396Z"},"source":{"advisory":"GHSA-4h8g-378q-r75m","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-01T17:05:19.453049Z","id":"CVE-2026-45104","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-01T17:08:18.608Z"}}]}}}