{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2023-4236",
        "ASSIGNER": "security-officer@isc.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "A flaw in the networking code handling DNS-over-TLS queries may cause `named` to terminate unexpectedly due to an assertion failure. This happens when internal data structures are incorrectly reused under significant DNS-over-TLS query load.\nThis issue affects BIND 9 versions 9.18.0 through 9.18.18 and 9.18.11-S1 through 9.18.18-S1."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "ISC",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "BIND 9",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<=",
                                            "version_name": "9.18.0",
                                            "version_value": "9.18.18"
                                        },
                                        {
                                            "version_affected": "<=",
                                            "version_name": "9.18.11-S1",
                                            "version_value": "9.18.18-S1"
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://kb.isc.org/docs/cve-2023-4236",
                "refsource": "MISC",
                "name": "https://kb.isc.org/docs/cve-2023-4236"
            },
            {
                "url": "http://www.openwall.com/lists/oss-security/2023/09/20/2",
                "refsource": "MISC",
                "name": "http://www.openwall.com/lists/oss-security/2023/09/20/2"
            },
            {
                "url": "https://www.debian.org/security/2023/dsa-5504",
                "refsource": "MISC",
                "name": "https://www.debian.org/security/2023/dsa-5504"
            },
            {
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IPJLLTJCSDJJII7IIZPLTBQNWP7MZH7F/",
                "refsource": "MISC",
                "name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IPJLLTJCSDJJII7IIZPLTBQNWP7MZH7F/"
            },
            {
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U35OARLQCPMVCBBPHWBXY5M6XJLD2TZ5/",
                "refsource": "MISC",
                "name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U35OARLQCPMVCBBPHWBXY5M6XJLD2TZ5/"
            },
            {
                "url": "https://security.netapp.com/advisory/ntap-20231013-0004/",
                "refsource": "MISC",
                "name": "https://security.netapp.com/advisory/ntap-20231013-0004/"
            },
            {
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VSK5V4W4OHPM3JTJGWAQD6CZW7SFD75B/",
                "refsource": "MISC",
                "name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VSK5V4W4OHPM3JTJGWAQD6CZW7SFD75B/"
            }
        ]
    },
    "source": {
        "discovery": "EXTERNAL"
    },
    "work_around": [
        {
            "lang": "en",
            "value": "Disabling listening for DNS-over-TLS connections (by removing `listen-on ... tls ... { ... };` statements from the configuration) prevents the affected code paths from being taken, rendering exploitation impossible. However, there is no workaround for this flaw if DNS-over-TLS support is required."
        }
    ],
    "exploit": [
        {
            "lang": "en",
            "value": "We are not aware of any active exploits."
        }
    ],
    "solution": [
        {
            "lang": "en",
            "value": "Upgrade to the patched release most closely related to your current version of BIND 9: 9.18.19 or 9.18.19-S1."
        }
    ],
    "credits": [
        {
            "lang": "en",
            "value": "ISC would like to thank Robert Story from the USC/ISI DNS root server operations team for bringing this vulnerability to our attention."
        }
    ],
    "impact": {
        "cvss": [
            {
                "version": "3.1",
                "attackVector": "NETWORK",
                "attackComplexity": "LOW",
                "privilegesRequired": "NONE",
                "userInteraction": "NONE",
                "scope": "UNCHANGED",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "availabilityImpact": "HIGH",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "baseScore": 7.5,
                "baseSeverity": "HIGH"
            }
        ]
    }
}