{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-13321",
        "assignerOrgId": "404fd4d2-a609-4245-b543-2c944a302a22",
        "state": "PUBLISHED",
        "assignerShortName": "isc",
        "dateReserved": "2026-06-25T08:45:35.931Z",
        "datePublished": "2026-07-22T14:16:10.450Z",
        "dateUpdated": "2026-07-22T18:51:47.414Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "404fd4d2-a609-4245-b543-2c944a302a22",
                "shortName": "isc",
                "dateUpdated": "2026-07-22T14:16:10.450Z"
            },
            "title": "DNSSEC Validation Bypass via Out-of-Zone NSEC Next Field",
            "datePublic": "2026-07-22T00:00:00.000Z",
            "affected": [
                {
                    "vendor": "ISC",
                    "product": "BIND 9",
                    "versions": [
                        {
                            "version": "9.11.0",
                            "lessThanOrEqual": "9.18.50",
                            "status": "affected",
                            "versionType": "custom"
                        },
                        {
                            "version": "9.20.0",
                            "lessThanOrEqual": "9.20.24",
                            "status": "affected",
                            "versionType": "custom"
                        },
                        {
                            "version": "9.21.0",
                            "lessThanOrEqual": "9.21.23",
                            "status": "affected",
                            "versionType": "custom"
                        },
                        {
                            "version": "9.11.3-S1",
                            "lessThanOrEqual": "9.18.50-S1",
                            "status": "affected",
                            "versionType": "custom"
                        },
                        {
                            "version": "9.20.9-S1",
                            "lessThanOrEqual": "9.20.24-S1",
                            "status": "affected",
                            "versionType": "custom"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "9.11.0",
                                    "versionEndIncluding": "9.18.50"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "9.20.0",
                                    "versionEndIncluding": "9.20.24"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "9.21.0",
                                    "versionEndIncluding": "9.21.23"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "9.11.3-S1",
                                    "versionEndIncluding": "9.18.50-S1"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "9.20.9-S1",
                                    "versionEndIncluding": "9.20.24-S1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "scope": "CHANGED",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "HIGH",
                        "availabilityImpact": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N",
                        "baseScore": 8.6,
                        "baseSeverity": "HIGH"
                    }
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "type": "CWE",
                            "cweId": "CWE-346",
                            "description": "CWE-346 Origin Validation Error"
                        }
                    ]
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "The BIND resolver accepts validly-signed NSEC records where the \"Next Domain Name\" field points outside the signer's zone.\nThis issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1."
                }
            ],
            "impacts": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "An attacker controlling any DNSSEC-signed zone can craft NSEC records that span into victim zones, enabling cross-zone cache poisoning with authenticated denial-of-service responses (AD=1)."
                        }
                    ]
                }
            ],
            "workarounds": [
                {
                    "lang": "en",
                    "value": "No workarounds known."
                }
            ],
            "exploits": [
                {
                    "lang": "en",
                    "value": "We are not aware of any active exploits."
                }
            ],
            "solutions": [
                {
                    "lang": "en",
                    "value": "Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.26, 9.21.24, or 9.20.26-S1."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "ISC would like to thank Qifan Zhang of Palo Alto Networks for bringing this vulnerability to our attention."
                }
            ],
            "references": [
                {
                    "url": "https://kb.isc.org/docs/cve-2026-13321",
                    "name": "CVE-2026-13321",
                    "tags": [
                        "vendor-advisory"
                    ]
                },
                {
                    "url": "https://downloads.isc.org/isc/bind9/9.20.26",
                    "tags": [
                        "patch"
                    ]
                },
                {
                    "url": "https://downloads.isc.org/isc/bind9/9.21.24",
                    "tags": [
                        "patch"
                    ]
                }
            ],
            "source": {
                "discovery": "EXTERNAL"
            },
            "x_generator": {
                "engine": "cvelib 1.8.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-22T18:51:32.344539Z",
                                "id": "CVE-2026-13321",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-07-22T18:51:47.414Z"
                }
            }
        ]
    }
}