CVE catalog

CVE-2026-45104

MapServer is a system for developing web-based GIS…

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: High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: May 27, 2026, 6:41:39 PM UTC
Source: [NVD] · [CVE record]
EPSS: 0.32% · Oct 27, 2026

Projects and upstream resources

[mapserver][Source-reported homepage]

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Version impact has not been established. The original provider fields are retained below.

Provider details and historical evidence

Original provider fields

{
  "package_releases": [
    {
      "name": "mapserver",
      "status": "fixed",
      "release": "sid",
      "version": "8.6.6-1"
    },
    {
      "name": "mapserver",
      "status": "fixed",
      "release": "forky",
      "version": "8.6.6-1"
    },
    {
      "name": "mapserver",
      "status": "vulnerable",
      "release": "trixie",
      "version": "8.4.0-4+deb13u2"
    },
    {
      "name": "mapserver",
      "status": "vulnerable",
      "release": "bookworm",
      "version": "8.0.0-3+deb12u1"
    }
  ],
  "fixed_versions": [
    {
      "bug": null,
      "name": "mapserver",
      "type": "source",
      "origin": null,
      "release": "sid",
      "urgency": "not yet assigned",
      "fixed_version": "8.6.3-1"
    },
    {
      "bug": null,
      "name": "mapserver",
      "type": "source",
      "origin": null,
      "release": "forky",
      "urgency": "not yet assigned",
      "fixed_version": "8.6.3-1"
    },
    {
      "bug": null,
      "name": "mapserver",
      "type": "source",
      "origin": null,
      "release": "trixie",
      "urgency": "not yet assigned",
      "fixed_version": ""
    },
    {
      "bug": null,
      "name": "mapserver",
      "type": "source",
      "origin": null,
      "release": "bookworm",
      "urgency": "not yet assigned",
      "fixed_version": ""
    }
  ],
  "distribution_packages": [
    {
      "name": "mapserver",
      "ecosystem": "cpe",
      "fixed_version": "not yet fixed"
    },
    {
      "name": "mapserver",
      "ecosystem": "cpe",
      "fixed_version": "8.6.3"
    }
  ]
}

Publisher notes

[trixie] mapserver: Minor issue [bookworm] mapserver: Minor issue, DoS in SLD ElseFilter parsing

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[cgi-mapserver]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[libmapscript-java]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[libmapscript-perl]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[libmapserver2]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[libmapserver-dev]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[mapserver-bin]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[mapserver-doc]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · all · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · all · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · all · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · all · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[php-mapscript-ng]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
[python3-mapscript]Unknown
Source package: [mapserver]
Details (4)
- 8.0.0-3+deb12u1 · amd64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.0.0-3+deb12u1 · arm64 · bookworm
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · amd64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12
- 8.4.0-1~bpo12+1 · arm64 · bookworm-backports
  Affected
  nvd · mapserver · debian · bookworm; nvd · mapserver · debian · 12

[Debian 13 (Trixie)]

[cgi-mapserver]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[libmapscript-java]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[libmapscript-perl]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[libmapserver2t64]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[libmapserver-dev]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[mapserver-bin]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[mapserver-doc]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · all · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · all · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · all · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · all · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[php-mapscript-ng]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
[python3-mapscript]Unknown
Source package: [mapserver]
Details (4)
- 8.4.0-4+deb13u2 · amd64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.4.0-4+deb13u2 · arm64 · trixie
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13
- 8.6.5-1~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · mapserver · debian · 13

Observed: Oct 23, 2026, 9:51:30 PM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]