CoreDNS DoH GET path missing size validation causes CPU and memory amplification_CVE-2026-32936

{
    "lastseen": "",
    "description": "CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the DNS-over-HTTPS (DoH) GET path accepts oversized dns= query parameter values and performs URL query parsing, base64 decoding, and DNS message unpacking before rejecting the request. Unlike the POST path, which applies a bounded read via http.MaxBytesReader limited to 65536 bytes, the GET path has no equivalent size validation before expensive processing. A remote, unauthenticated attacker can repeatedly send oversized DoH GET requests to force high CPU usage, large transient memory allocations, and elevated garbage-collection pressure, leading to denial of service. This issue has been fixed in version 1.14.3.",
    "published": "2026-05-05T19:07:51.926Z",
    "modified": "2026-05-05T19:07:51.926Z",
    "type": "cve",
    "title": "CoreDNS DoH GET path missing size validation causes CPU and memory amplification",
    "source": "GitHub_M",
    "references": "https://github.com/coredns/coredns/security/advisories/GHSA-63cw-r7xf-jmwr\nhttps://github.com/coredns/coredns/releases/tag/v1.14.3",
    "id": "CVE-2026-32936",
    "bulletinFamily": "",
    "cwe": [
        "CWE-400"
    ],
    "cvelist": null,
    "sourceData": "coredns coredns < 1.14.3",
    "sourceHref": "",
    "cvss": {
        "score": 8.7,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
        "version": "4.0"
    },
    "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": "coredns",
    "version": "< 1.14.3",
    "vendor": "coredns",
    "ai_description": "A remote, unauthenticated attacker can send oversized DoH GET requests to cause denial of service in CoreDNS versions prior to 1.14.3.",
    "ai_severity": "High",
    "ai_vendor": "CoreDNS Team",
    "ai_product": "CoreDNS",
    "ai_version": "< 1.14.3",
    "ai_score": 8.7
}