{"id":"DEBIAN-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":"2026-09-14T17:03:42.162210703Z","published":"2026-05-27T20:16:38.407Z","upstream":["CVE-2026-45104"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-45104"}],"affected":[{"package":{"name":"mapserver","ecosystem":"Debian:12","purl":"pkg:deb/debian/mapserver?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.0.0-3","8.0.0-3+deb12u1","8.0.1-1","8.0.1-1~exp1","8.0.1-2","8.0.1-2.1~exp1","8.0.1-2~bpo12+1","8.0.1-3","8.0.1-3~exp1","8.0.1-4","8.0.1-5","8.0.2-1","8.0.2-1~bpo12+1","8.2.0-1","8.2.0-1~bpo12+1","8.2.0~beta1-1~exp1","8.2.0~beta2-1~exp1","8.2.0~beta3-1~exp1","8.2.0~rc1-1~exp1","8.2.0~rc2-1~exp1","8.2.0~rc3-1~exp1","8.2.1-1","8.2.1-1~bpo12+1","8.2.2-1","8.2.2-1~bpo12+1","8.4.0-1","8.4.0-1~bpo12+1","8.4.0-2","8.4.0-3","8.4.0-4","8.4.0~beta1-1~exp1","8.4.0~beta2-1~exp1","8.4.0~rc1-1~exp1","8.4.1-1","8.4.1-1~bpo13+1","8.4.1-2","8.6.0-1","8.6.0-1~bpo13+1","8.6.0~beta1-1~exp1","8.6.0~beta2-1~exp1","8.6.0~rc1-1~exp1","8.6.1-1","8.6.1-1~bpo13+1","8.6.2-1","8.6.2-1~bpo13+1","8.6.3-1","8.6.3-1~bpo13+1","8.6.4-1","8.6.4-1~bpo13+1","8.6.5-1","8.6.5-1~bpo13+1","8.6.6-1","8.6.6-1~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-45104.json"}},{"package":{"name":"mapserver","ecosystem":"Debian:13","purl":"pkg:deb/debian/mapserver?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.4.0-4","8.4.0-4+deb13u1","8.4.0-4+deb13u2","8.4.1-1","8.4.1-1~bpo13+1","8.4.1-2","8.6.0-1","8.6.0-1~bpo13+1","8.6.0~beta1-1~exp1","8.6.0~beta2-1~exp1","8.6.0~rc1-1~exp1","8.6.1-1","8.6.1-1~bpo13+1","8.6.2-1","8.6.2-1~bpo13+1","8.6.3-1","8.6.3-1~bpo13+1","8.6.4-1","8.6.4-1~bpo13+1","8.6.5-1","8.6.5-1~bpo13+1","8.6.6-1","8.6.6-1~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-45104.json"}},{"package":{"name":"mapserver","ecosystem":"Debian:14","purl":"pkg:deb/debian/mapserver?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.6.3-1"}]}],"versions":["8.4.0-4","8.4.1-1","8.4.1-1~bpo13+1","8.4.1-2","8.6.0-1","8.6.0-1~bpo13+1","8.6.0~beta1-1~exp1","8.6.0~beta2-1~exp1","8.6.0~rc1-1~exp1","8.6.1-1","8.6.1-1~bpo13+1","8.6.2-1","8.6.2-1~bpo13+1","8.6.3-1~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-45104.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}