CVE-2026-128089 (GCVE-0-2026-128089)

Vulnerability from cvelistv5 – Published: 2026-11-13 19:22 – Updated: 2026-11-13 19:22
VLAI
Title
dnspython excessive memory and CPU use
Summary
dnspython is a DNS toolkit for Python. Prior to version 2.9.2, the from_text() parser for WKS records does not require the service number to be between 0 and 65535 before using it as a bitmap offset. An attacker-controlled zone file can supply a larger number, causing the service bitmap to grow to an extremely large size through inefficient repeated extension, consuming excessive memory and CPU and potentially terminating the process. Applications are affected only when they parse zone-file text whose record type and rdata are attacker controlled. This issue is fixed in version 2.9.2.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rthalley dnspython Affected: < 2.9.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
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      "affected": [
        {
          "product": "dnspython",
          "vendor": "rthalley",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.9.2"
            }
          ]
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      ],
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          "lang": "en",
          "value": "dnspython is a DNS toolkit for Python. Prior to version 2.9.2, the from_text() parser for WKS records does not require the service number to be between 0 and 65535 before using it as a bitmap offset. An attacker-controlled zone file can supply a larger number, causing the service bitmap to grow to an extremely large size through inefficient repeated extension, consuming excessive memory and CPU and potentially terminating the process. Applications are affected only when they parse zone-file text whose record type and rdata are attacker controlled. This issue is fixed in version 2.9.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "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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              "description": "CWE-400: Uncontrolled Resource Consumption",
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              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-13T19:22:22.444Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/rthalley/dnspython/security/advisories/GHSA-vvf4-9x63-8xvv",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/rthalley/dnspython/security/advisories/GHSA-vvf4-9x63-8xvv"
        },
        {
          "name": "https://github.com/rthalley/dnspython/commit/388db14ee9923288f6e73f86e482c77706e59d73",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/rthalley/dnspython/commit/388db14ee9923288f6e73f86e482c77706e59d73"
        },
        {
          "name": "https://github.com/rthalley/dnspython/commit/a62e1be066da0ed71b5b59f37435bb17cfa0070f",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/rthalley/dnspython/commit/a62e1be066da0ed71b5b59f37435bb17cfa0070f"
        },
        {
          "name": "https://github.com/rthalley/dnspython/releases/tag/v2.9.2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/rthalley/dnspython/releases/tag/v2.9.2"
        }
      ],
      "source": {
        "advisory": "GHSA-vvf4-9x63-8xvv",
        "discovery": "UNKNOWN"
      },
      "title": "dnspython excessive memory and CPU use"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-128089",
    "datePublished": "2026-11-13T19:22:22.444Z",
    "dateReserved": "2026-11-12T21:24:51.131Z",
    "dateUpdated": "2026-11-13T19:22:22.444Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "dnspython",
                "vendor": "rthalley",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003c 2.9.2"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "dnspython is a DNS toolkit for Python. Prior to version 2.9.2, the from_text() parser for WKS records does not require the service number to be between 0 and 65535 before using it as a bitmap offset. An attacker-controlled zone file can supply a larger number, causing the service bitmap to grow to an extremely large size through inefficient repeated extension, consuming excessive memory and CPU and potentially terminating the process. Applications are affected only when they parse zone-file text whose record type and rdata are attacker controlled. This issue is fixed in version 2.9.2."
          }
        ],
        "id": "CVE-2026-128089",
        "lastModified": "2026-11-13T20:18:55.913",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "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"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 3.6,
              "source": "security-advisories@github.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-11-13T20:18:55.913",
        "references": [
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/rthalley/dnspython/commit/388db14ee9923288f6e73f86e482c77706e59d73"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/rthalley/dnspython/commit/a62e1be066da0ed71b5b59f37435bb17cfa0070f"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/rthalley/dnspython/releases/tag/v2.9.2"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/rthalley/dnspython/security/advisories/GHSA-vvf4-9x63-8xvv"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-400"
              },
              {
                "lang": "en",
                "value": "CWE-770"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Primary"
          }
        ]
      }
    }
  }
}



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