CVE-2026-40198

{
  "id": "CVE-2026-40198",
  "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
  "published": "2026-04-10T22:16:21.463",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass.\n\n_pack_ipv6() does not check that uncompressed IPv6 addresses (without ::) have exactly 8 hex groups. Inputs like \"abcd\", \"1:2:3\", or \"1:2:3:4:5:6:7\" are accepted and produce packed values of wrong length (3, 7, or 15 bytes instead of 17).\n\nThe packed values are used internally for mask and comparison operations. find() and bin_find() use Perl string comparison (lt/gt) on these values, and comparing strings of different lengths gives wrong results. This can cause find() to incorrectly report an address as inside or outside a range.\n\nExample:\n\n  my $cidr = Net::CIDR::Lite->new(\"::/8\");\n  $cidr->find(\"1:2:3\");  # invalid input, incorrectly returns true\n\nThis is the same class of input validation issue as CVE-2021-47154 (IPv4 leading zeros) previously fixed in this module.\n\nSee also CVE-2026-40199, a related issue in the same function affecting IPv4 mapped IPv6 addresses."
    },
    {
      "lang": "es",
      "value": "Las versiones de Net::CIDR::Lite anteriores a la 0.23 para Perl no validan el recuento de grupos IPv6, lo que puede permitir la omisión de ACL de IP.\n\n_pack_ipv6() no comprueba que las direcciones IPv6 sin comprimir (sin ::) tengan exactamente 8 grupos hexadecimales. Entradas como ’abcd’, ’1:2:3’ o ’1:2:3:4:5:6:7’ son aceptadas y producen valores empaquetados de longitud incorrecta (3, 7 o 15 bytes en lugar de 17).\n\nLos valores empaquetados se utilizan internamente para operaciones de máscara y comparación. find() y bin_find() utilizan la comparación de cadenas de Perl (lt/gt) en estos valores, y comparar cadenas de diferentes longitudes produce resultados incorrectos. Esto puede hacer que find() informe incorrectamente una dirección como dentro o fuera de un rango.\n\nEjemplo:\n\n  my $cidr = Net::CIDR::Lite -> new(’::/8’);\n  $cidr -> find(’1:2:3’); # entrada inválida, devuelve true incorrectamente\n\nEsta es la misma clase de problema de validación de entrada que CVE-2021-47154 (ceros iniciales de IPv4) corregido previamente en este módulo.\n\nVéase también CVE-2026-40199, un problema relacionado en la misma función que afecta a las direcciones IPv6 mapeadas a IPv4."
    }
  ],
  "affected": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "affectedData": [
        {
          "vendor": "STIGTSP",
          "product": "Net::CIDR::Lite",
          "defaultStatus": "unaffected",
          "collectionURL": "https://cpan.org/modules",
          "packageName": "Net-CIDR-Lite",
          "programFiles": [
            "Lite.pm"
          ],
          "programRoutines": [
            {
              "name": "Net::CIDR::Lite::_pack_ipv6"
            }
          ],
          "repo": "https://github.com/stigtsp/Net-CIDR-Lite",
          "versions": [
            {
              "version": "0",
              "lessThan": "0.23",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-13T14:41:19.772152Z",
          "id": "CVE-2026-40198",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-1286"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:stigtsp:net\\:\\:cidr\\:\\:lite:*:*:*:*:*:perl:*:*",
              "versionEndExcluding": "0.23",
              "matchCriteriaId": "2B8C0BC5-5E3C-4399-9FD6-437BFF65130F"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/stigtsp/Net-CIDR-Lite/commit/25d65f85dbe4885959a10471725ec9d250a589c3.patch",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://metacpan.org/release/STIGTSP/Net-CIDR-Lite-0.23/changes",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "tags": [
        "Release Notes"
      ]
    },
    {
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-40199",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "tags": [
        "Third Party Advisory"
      ]
    }
  ]
}