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CVE-2026-19941 (GCVE-0-2026-19941)

Vulnerability from cvelistv5 – Published: 2026-09-16 13:52 – Updated: 2026-09-16 13:52
VLAI
Title
checkwildcard() accepts an out-of-zone NSEC as a wildcard-nonexistence proof
Summary
An inapplicable NSEC record may be accepted by a `named` resolver as proof that no wildcard exists, which could allow an attacker at the same or an upstream level of the zone name to mask the existence of a victim's wildcard record. 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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
References
Impacted products
Vendor Product Version CPE status
ISC BIND 9 Affected: 9.11.0 , ≤ 9.18.50 (custom)
Affected: 9.20.0 , ≤ 9.20.27 (custom)
Affected: 9.21.0 , ≤ 9.21.25 (custom)
Affected: 9.11.3-S1 , ≤ 9.18.50-S1 (custom)
Affected: 9.20.9-S1 , ≤ 9.20.27-S1 (custom)
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-16 00:00
Show details on NVD website
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  "containers": {
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      "affected": [
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          "defaultStatus": "unaffected",
          "product": "BIND 9",
          "vendor": "ISC",
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              "status": "affected",
              "version": "9.20.0",
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      "descriptions": [
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      "exploits": [
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          "value": "This flaw was discovered in internal testing. We are not aware of any active exploits."
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      "impacts": [
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      "metrics": [
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            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
            "version": "3.1"
          }
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      "problemTypes": [
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          "descriptions": [
            {
              "cweId": "CWE-345",
              "description": "CWE-345 Insufficient Verification of Data Authenticity",
              "lang": "en",
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      "providerMetadata": {
        "dateUpdated": "2026-09-16T13:52:49.400Z",
        "orgId": "404fd4d2-a609-4245-b543-2c944a302a22",
        "shortName": "isc"
      },
      "references": [
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          "name": "CVE-2026-19941",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://kb.isc.org/docs/cve-2026-19941"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://downloads.isc.org/isc/bind9/9.20.29"
        },
        {
          "tags": [
            "patch"
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          "url": "https://downloads.isc.org/isc/bind9/9.21.26"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.29, 9.21.26, or 9.20.29-S1."
        }
      ],
      "source": {
        "discovery": "INTERNAL"
      },
      "title": "checkwildcard() accepts an out-of-zone NSEC as a wildcard-nonexistence proof",
      "workarounds": [
        {
          "lang": "en",
          "value": "No workarounds known."
        }
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    "cveId": "CVE-2026-19941",
    "datePublished": "2026-09-16T13:52:49.400Z",
    "dateReserved": "2026-08-15T14:30:38.165Z",
    "dateUpdated": "2026-09-16T13:52:49.400Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-16T20:07:02+00:00",
      "cve": "CVE-2026-19941",
      "id": "CVE-2026-19941",
      "initial_release_date": "2026-09-16T13:52:49.400000+00:00",
      "product_status:under_investigation": "88",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "bind9: bind: BIND 9: DNS wildcard record existence can be masked by an attacker via inapplicable NSEC records",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-19941.json",
      "version": "3"
    }
  }
}



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