{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:osgeo:mapserver:*:*:*:*:*:*:*:*",
            "extracted_events": [
              {
                "introduced": "6.4.0"
              },
              {
                "fixed": "8.6.3"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "CPE_RANGE"
            ]
          },
          "events": [
            {
              "introduced": "a098e546885dd7244ce6174ec11e6f0410879a41"
            },
            {
              "fixed": "d83a1b9ce1301e6f941a1a8ea787fd209f7ecfba"
            }
          ],
          "repo": "https://github.com/mapserver/mapserver",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-4h8g-378q-r75m"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-129",
      "CWE-476"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45104.json"
  },
  "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.",
  "id": "CVE-2026-45104",
  "modified": "2026-07-08T05:37:21.150421405Z",
  "published": "2026-05-27T18:41:39.396Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45104.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/MapServer/MapServer/security/advisories/GHSA-4h8g-378q-r75m"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45104"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "MapServer: NULL pointer dereference in SLD `\u003cElseFilter\u003e` rule parsing reachable via WMS `SLD_BODY`"
}