MapServer has heap buffer overflow in SLD `Categorize` Threshold parsing_CVE-2026-33721

{
    "lastseen": "",
    "description": "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\u2019s 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.",
    "published": "2026-03-27T00:15:00.360Z",
    "modified": "2026-03-30T11:52:01.621Z",
    "type": "cve",
    "title": "MapServer has heap buffer overflow in SLD `Categorize` Threshold parsing",
    "source": "GitHub_M",
    "references": "https://github.com/MapServer/MapServer/security/advisories/GHSA-cv4m-mr84-fgjp\nhttps://github.com/MapServer/MapServer/releases/tag/rel-8-6-1",
    "id": "CVE-2026-33721",
    "bulletinFamily": "",
    "cwe": [
        "CWE-787"
    ],
    "cvelist": null,
    "sourceData": "MapServer MapServer >= 4.2, < 8.6.1",
    "sourceHref": "",
    "cvss": {
        "score": 5.3,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "MapServer",
    "version": ">= 4.2, < 8.6.1",
    "vendor": "MapServer",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}