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
Linked Vulnerabilities

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  "datePublished": "2026-07-22T15:16:51.703",
  "dateUpdated": "2026-11-02T17:42:50.153",
  "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.\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.",
  "id": "CVE-2026-11622",
  "raw": {
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        "lang": "en",
        "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."
      },
      {
        "lang": "es",
        "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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    "id": "CVE-2026-11622",
    "lastModified": "2026-11-02T17:42:50.153",
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            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "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",
            "version": "3.1"
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            "role": "CISA Coordinator",
            "timestamp": "2026-07-22T18:53:04.346058Z",
            "version": "2.0.3"
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    "published": "2026-07-22T15:16:51.703",
    "references": [
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        "source": "security-officer@isc.org",
        "tags": [
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        "url": "https://downloads.isc.org/isc/bind9/9.20.26"
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        "url": "https://kb.isc.org/docs/cve-2026-11622"
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  "severity": "HIGH",
  "source": "nvd",
  "title": "A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from run..."
}
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