CVE-2026-19033
Full vulnerability record from the local CVENow database.
Description
For a secondary zone with transfers restricted by TSIG, `named` may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to a secondary server. Although no TSIG signature ever arrives, `named` does not rollback to the pre-transfer state. To exploit the vulnerability, the transfer must be a multi-message TCP IXFR, as described by RFC 8945. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.
View original CVE JSON
{
"id": "CVE-2026-19033",
"sourceIdentifier": "[email protected]",
"published": "2026-09-16T15:17:33.393",
"lastModified": "2026-10-26T23:10:00.183",
"vulnStatus": "Awaiting Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "For a secondary zone with transfers restricted by TSIG, `named` may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to a secondary server. Although no TSIG signature ever arrives, `named` does not rollback to the pre-transfer state. To exploit the vulnerability, the transfer must be a multi-message TCP IXFR, as described by RFC 8945.\nThis issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1."
},
{
"lang": "es",
"value": "Para una zona secundaria con transferencias restringidas por TSIG, “named” puede comenzar a servir los datos proporcionados en una transferencia de zona antes de que llegue el mensaje final con la firma TSIG. Esto podría permitir a un atacante que no posee una firma TSIG válida enviar contenidos de zona no autorizados a un servidor secundario. Aunque nunca llega una firma TSIG, “named” no revierte al estado previo a la transferencia. Para explotar la vulnerabilidad, la transferencia debe ser una IXFR TCP de varios mensajes, según lo descrito en la RFC?8945. Este problema afecta a BIND?9 desde la versión?9.11.0 hasta la?9.18.50 incluida, desde la versión?9.20.0 hasta la?9.20.27 incluida, desde la versión?9.21.0 hasta la?9.21.25 incluida, desde la versión?9.11.3?S1 hasta la?9.18.50?S1 incluida, y desde la versión?9.20.9?S1 hasta la?9.20.27?S1 incluida."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "ISC",
"product": "BIND 9",
"defaultStatus": "unaffected",
"versions": [
{
"version": "9.11.0",
"lessThanOrEqual": "9.18.50",
"versionType": "custom",
"status": "affected"
},
{
"version": "9.20.0",
"lessThanOrEqual": "9.20.27",
"versionType": "custom",
"status": "affected"
},
{
"version": "9.21.0",
"lessThanOrEqual": "9.21.25",
"versionType": "custom",
"status": "affected"
},
{
"version": "9.11.3-S1",
"lessThanOrEqual": "9.18.50-S1",
"versionType": "custom",
"status": "affected"
},
{
"version": "9.20.9-S1",
"lessThanOrEqual": "9.20.27-S1",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"availabilityImpact": "LOW"
},
"exploitabilityScore": 2.2,
"impactScore": 4.2
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-09-17T17:36:40.215995Z",
"id": "CVE-2026-19033",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-349"
}
]
}
],
"references": [
{
"url": "https://downloads.isc.org/isc/bind9/9.20.29",
"source": "[email protected]"
},
{
"url": "https://downloads.isc.org/isc/bind9/9.21.26",
"source": "[email protected]"
},
{
"url": "https://kb.isc.org/docs/cve-2026-19033",
"source": "[email protected]"
}
]
}