Vulnerability-Lookup

GHSA-8P39-MP4Q-99C8

Vulnerability from github – Published: 2026-07-22 15:31 – Updated: 2026-07-22 15:31

Details

An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software. This issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.16.8-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-11331"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-790"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-22T15:16:51Z",
    "severity": "HIGH"
  },
  "details": "An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software.\nThis issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.16.8-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.",
  "id": "GHSA-8p39-mp4q-99c8",
  "modified": "2026-07-22T15:31:26Z",
  "published": "2026-07-22T15:31:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-11331"
    },
    {
      "type": "WEB",
      "url": "https://downloads.isc.org/isc/bind9/9.20.26"
    },
    {
      "type": "WEB",
      "url": "https://downloads.isc.org/isc/bind9/9.21.24"
    },
    {
      "type": "WEB",
      "url": "https://kb.isc.org/docs/cve-2026-11331"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-11331 (GCVE-0-2026-11331)

Vulnerability from cvelistv5 – Published: 2026-07-22 14:10 – Updated: 2026-07-22 18:54

Title

Potential wildcard CNAME RPZ policy bypass

Summary

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-22 18:54 UTC

CWE

CWE-790 - Improper Filtering of Special Elements

Assigner

isc mitre root

References

3 references

URL	Tags
https://kb.isc.org/docs/cve-2026-11331	vendor-advisory
https://downloads.isc.org/isc/bind9/9.20.26	patch
https://downloads.isc.org/isc/bind9/9.21.24	patch

Impacted products

1 product

Vendor	Product	Version
ISC	BIND 9	Affected: 9.16.0 , ≤ 9.18.50 (custom) Affected: 9.20.0 , ≤ 9.20.24 (custom) Affected: 9.21.0 , ≤ 9.21.23 (custom) Affected: 9.16.8-S1 , ≤ 9.18.50-S1 (custom) Affected: 9.20.9-S1 , ≤ 9.20.24-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::::::::

Date Public

2026-07-22 00:00

Credits

ISC would like to thank Laith Mash'al (0xmshal) for bringing this vulnerability to our attention.

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-11331",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-22T18:54:08.280433Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-22T18:54:17.064Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "BIND 9",
          "vendor": "ISC",
          "versions": [
            {
              "lessThanOrEqual": "9.18.50",
              "status": "affected",
              "version": "9.16.0",
              "versionType": "custom"
            },
            {
              "lessThanOrEqual": "9.20.24",
              "status": "affected",
              "version": "9.20.0",
              "versionType": "custom"
            },
            {
              "lessThanOrEqual": "9.21.23",
              "status": "affected",
              "version": "9.21.0",
              "versionType": "custom"
            },
            {
              "lessThanOrEqual": "9.18.50-S1",
              "status": "affected",
              "version": "9.16.8-S1",
              "versionType": "custom"
            },
            {
              "lessThanOrEqual": "9.20.24-S1",
              "status": "affected",
              "version": "9.20.9-S1",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "9.18.50",
                  "versionStartIncluding": "9.16.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "9.20.24",
                  "versionStartIncluding": "9.20.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "9.21.23",
                  "versionStartIncluding": "9.21.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "9.18.50-S1",
                  "versionStartIncluding": "9.16.8-S1",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "9.20.24-S1",
                  "versionStartIncluding": "9.20.9-S1",
                  "vulnerable": true
                }
              ],
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "ISC would like to thank Laith Mash\u0027al (0xmshal) for bringing this vulnerability to our attention."
        }
      ],
      "datePublic": "2026-07-22T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software.\nThis issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.16.8-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "We are not aware of any active exploits."
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "If such a situation is encountered, the targeted RPZ rule may be bypassed.  The condition could also lead to an unexpected exit."
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-790",
              "description": "CWE-790 Improper Filtering of Special Elements",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-22T14:10:44.763Z",
        "orgId": "404fd4d2-a609-4245-b543-2c944a302a22",
        "shortName": "isc"
      },
      "references": [
        {
          "name": "CVE-2026-11331",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://kb.isc.org/docs/cve-2026-11331"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://downloads.isc.org/isc/bind9/9.20.26"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://downloads.isc.org/isc/bind9/9.21.24"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.26, 9.21.24, or 9.20.26-S1."
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Potential wildcard CNAME RPZ policy bypass",
      "workarounds": [
        {
          "lang": "en",
          "value": "No workarounds known."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "404fd4d2-a609-4245-b543-2c944a302a22",
    "assignerShortName": "isc",
    "cveId": "CVE-2026-11331",
    "datePublished": "2026-07-22T14:10:44.763Z",
    "dateReserved": "2026-06-05T07:03:42.361Z",
    "dateUpdated": "2026-07-22T18:54:17.064Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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GHSA-8P39-MP4Q-99C8

CVE-2026-11331 (GCVE-0-2026-11331)

Tags

Sightings

Nomenclature

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