{"id":"UBUNTU-CVE-2026-45104","details":"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 \u003cRule\u003e carrying \u003cElseFilter/\u003e — 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.","modified":"2026-06-12T09:01:27.092134612Z","published":"2026-05-27T20:16:00Z","upstream":["CVE-2026-45104"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-45104"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-45104"},{"type":"REPORT","url":"https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m"}],"affected":[{"package":{"name":"mapserver","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/mapserver?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.0.0-4build1","7.0.0-5ubuntu1","7.0.0-7","7.0.0-8","7.0.0-8build1","7.0.0-9","7.0.0-9ubuntu1","7.0.0-9ubuntu2","7.0.0-9ubuntu3","7.0.0-9ubuntu3.1"],"ecosystem_specific":{"binaries":[{"binary_name":"cgi-mapserver","binary_version":"7.0.0-9ubuntu3.1"},{"binary_name":"libmapscript-java","binary_version":"7.0.0-9ubuntu3.1"},{"binary_version":"7.0.0-9ubuntu3.1","binary_name":"libmapscript-perl"},{"binary_name":"libmapserver2","binary_version":"7.0.0-9ubuntu3.1"},{"binary_version":"7.0.0-9ubuntu3.1","binary_name":"mapserver-bin"},{"binary_version":"7.0.0-9ubuntu3.1","binary_name":"python-mapscript"},{"binary_name":"ruby-mapscript","binary_version":"7.0.0-9ubuntu3.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45104.json"}},{"package":{"name":"mapserver","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/mapserver?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.0.6-2build1","7.0.7-1","7.0.7-1build1","7.0.7-1build2"],"ecosystem_specific":{"binaries":[{"binary_name":"cgi-mapserver","binary_version":"7.0.7-1build2"},{"binary_name":"libmapscript-java","binary_version":"7.0.7-1build2"},{"binary_name":"libmapscript-perl","binary_version":"7.0.7-1build2"},{"binary_name":"libmapserver2","binary_version":"7.0.7-1build2"},{"binary_name":"mapserver-bin","binary_version":"7.0.7-1build2"},{"binary_name":"python-mapscript","binary_version":"7.0.7-1build2"},{"binary_name":"ruby-mapscript","binary_version":"7.0.7-1build2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45104.json"}},{"package":{"name":"mapserver","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/mapserver?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.4.1-1build1","7.4.1-1build3","7.4.2-1","7.4.2-1build1","7.4.3-1","7.4.3-1build2","7.4.3-2","7.4.3-2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"cgi-mapserver","binary_version":"7.4.3-2build1"},{"binary_version":"7.4.3-2build1","binary_name":"libmapscript-java"},{"binary_name":"libmapscript-perl","binary_version":"7.4.3-2build1"},{"binary_version":"7.4.3-2build1","binary_name":"libmapserver2"},{"binary_version":"7.4.3-2build1","binary_name":"mapserver-bin"},{"binary_name":"php-mapscript","binary_version":"7.4.3-2build1"},{"binary_name":"php-mapscript-ng","binary_version":"7.4.3-2build1"},{"binary_version":"7.4.3-2build1","binary_name":"python3-mapscript"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45104.json"}},{"package":{"name":"mapserver","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/mapserver?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.6.3-1~exp1ubuntu1","7.6.4-2","7.6.4-2build2"],"ecosystem_specific":{"binaries":[{"binary_name":"cgi-mapserver","binary_version":"7.6.4-2build2"},{"binary_version":"7.6.4-2build2","binary_name":"libmapscript-java"},{"binary_name":"libmapscript-perl","binary_version":"7.6.4-2build2"},{"binary_name":"libmapserver2","binary_version":"7.6.4-2build2"},{"binary_name":"mapserver-bin","binary_version":"7.6.4-2build2"},{"binary_name":"python3-mapscript","binary_version":"7.6.4-2build2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45104.json"}},{"package":{"name":"mapserver","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/mapserver?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.0.1-2build1","8.0.1-2build2","8.0.1-2build3","8.0.1-2build5","8.0.1-4ubuntu1","8.0.1-4ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"cgi-mapserver","binary_version":"8.0.1-4ubuntu2"},{"binary_version":"8.0.1-4ubuntu2","binary_name":"libmapscript-java"},{"binary_name":"libmapscript-perl","binary_version":"8.0.1-4ubuntu2"},{"binary_name":"libmapserver2t64","binary_version":"8.0.1-4ubuntu2"},{"binary_name":"mapserver-bin","binary_version":"8.0.1-4ubuntu2"},{"binary_version":"8.0.1-4ubuntu2","binary_name":"php-mapscript-ng"},{"binary_version":"8.0.1-4ubuntu2","binary_name":"python3-mapscript"}]},"database_specific":{"source":"https://github.com/canonica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