| Name | CVE-2026-45104 |
| 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| mapserver (PTS) | bullseye | 7.6.2-1 | vulnerable |
| bullseye (security) | 7.6.2-1+deb11u2 | vulnerable | |
| bookworm | 8.0.0-3+deb12u1 | vulnerable | |
| trixie | 8.4.0-4+deb13u2 | vulnerable | |
| forky | 8.6.3-1 | fixed | |
| sid | 8.6.4-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| mapserver | source | (unstable) | 8.6.3-1 |
https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m