cve-2026-11622
HIGH CVSS 7.5 nvd
Description
A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured in the `max-cache-size` parameter. This 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.
Timeline
- Published
- 2026-07-22
- Last Modified
- 2026-11-02
CVSS Details
- Attack Vector
- NETWORK
- Attack Complexity
- LOW
- Privileges Required
- NONE
Affected Products
- isc bind
Weaknesses (CWE)
CVSS metrics
| Version | Base | Severity | Vector | Exploitability | Impact | Source |
|---|---|---|---|---|---|---|
| 3.1 | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
3.9 | 3.6 | security-officer@isc.org |
CPE configurations
OR
| CPE | Version range | Vulnerable |
|---|---|---|
cpe:2.3:a:isc:bind:*:*:*:*:supported_preview:*:*:* |
>= 9.11.3, <= 9.18.50 | yes |
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* |
>= 9.18.0, <= 9.18.50 | yes |
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* |
>= 9.20.0, <= 9.20.24 | yes |
cpe:2.3:a:isc:bind:*:*:*:*:supported_preview:*:*:* |
>= 9.20.9, <= 9.20.24 | yes |
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* |
>= 9.21.0, <= 9.21.23 | yes |
NVD metadata
- NVD status
- Analyzed
- Source identifier
security-officer@isc.org
References
- https://downloads.isc.org/isc/bind9/9.20.26 Product
- https://downloads.isc.org/isc/bind9/9.21.24 Product
- https://kb.isc.org/docs/cve-2026-11622 Vendor Advisory
Linked Vulnerabilities
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"datePublished": "2026-07-22T15:16:51.703",
"dateUpdated": "2026-11-02T17:42:50.153",
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"id": "CVE-2026-11622",
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"value": "A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured in the `max-cache-size` parameter.\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."
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"value": "Un resolvedor validador de DNSSEC que está bajo un ataque de subdominio aleatorio contra una zona firmada con DNSSEC puede sufrir un uso descontrolado de la memoria. El atacante necesita poder enviar consultas más rápido de lo que el resolvedor puede realizar la validación. El aumento del uso de memoria puede ser órdenes de magnitud más allá del límite configurado en el parámetro “max-cache-size”.\nEste problema afecta a las versiones de BIND 9 9.11.0 a 9.18.50, 9.20.0 a 9.20.24, 9.21.0 a 9.21.23, 9.11.3-S1 a 9.18.50-S1, y 9.20.9-S1 a 9.20.24-S1."
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"lastModified": "2026-11-02T17:42:50.153",
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"availabilityImpact": "HIGH",
"baseScore": 7.5,
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"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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"timestamp": "2026-07-22T18:53:04.346058Z",
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"source": "nvd",
"title": "A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from run..."
}