{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "4.2"
              },
              {
                "fixed": "8.6.1"
              }
            ]
          },
          "events": [
            {
              "introduced": "8d58e49d129e88e3d319f02be3c8ca65ae7d6de8"
            },
            {
              "fixed": "292d06f99f427ff4ea54720849659cbd9f8cfef8"
            }
          ],
          "repo": "https://github.com/mapserver/mapserver",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-cv4m-mr84-fgjp"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33721.json"
  },
  "details": "MapServer is a system for developing web-based GIS applications. Starting in version 4.2 and prior to version 8.6.1, a heap-buffer-overflow write in MapServer’s SLD (Styled Layer Descriptor) parser lets a remote, unauthenticated attacker crash the MapServer process by sending a crafted SLD with more than 100 Threshold elements inside a ColorMap/Categorize structure (commonly reachable via WMS GetMap with SLD_BODY). Version 8.6.1 patches the issue.",
  "id": "CVE-2026-33721",
  "modified": "2026-04-01T23:08:58.124950933Z",
  "published": "2026-03-27T00:15:00.360Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33721.json"
    },
    {
      "type": "WEB",
      "url": "https://github.com/MapServer/MapServer/releases/tag/rel-8-6-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/MapServer/MapServer/security/advisories/GHSA-cv4m-mr84-fgjp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33721"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "MapServer has heap buffer overflow in SLD `Categorize` Threshold parsing"
}