CVE-2026-19027

{
  "id": "CVE-2026-19027",
  "sourceIdentifier": "0253b833-3e77-4dfe-9d57-17db1a2f0a74",
  "published": "2026-08-06T00:16:53.253",
  "lastModified": "2026-10-23T21:10:00.157",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The H5Z__nbit_decompress_one_byte, H5Z__nbit_decompress_one_nooptype, and H5Z__nbit_decompress_one_atomic functions in H5Znbit.c in HDF5\nprior to 2.3.0 advance a read index into the compressed chunk buffer without bounding it against the buffer's actual size. This allows attackers to cause an out-of-bounds heap read, and in constrained cases disclosure of adjacent heap memory into decompressed dataset values, via a crafted HDF5 file whose N-Bit filter parameters describe more decompressed data than the stored compressed chunk actually contains, triggered via H5Dread, e.g. by the h5ls or h5repack tools."
    },
    {
      "lang": "es",
      "value": "Las funciones H5Z__nbit_decompress_one_byte, H5Z__nbit_decompress_one_nooptype y H5Z__nbit_decompress_one_atomic en H5Znbit.c de HDF5, en versiones anteriores a 2.3.0, avanzan un índice de lectura en el búfer de fragmentos comprimidos sin limitarlo al tamaño real del búfer. Esto permite a los atacantes provocar una lectura de pila fuera de límites (out-of-bounds heap read) y, en casos restringidos, la divulgación de memoria de pila adyacente en valores de conjuntos de datos descomprimidos, a través de un archivo HDF5 manipulado cuyos parámetros de filtro N-Bit describen más datos descomprimidos de los que el fragmento comprimido almacenado contiene realmente, lo que se activa a través de H5Dread, por ejemplo, mediante las herramientas h5ls o h5repack."
    }
  ],
  "affected": [
    {
      "source": "0253b833-3e77-4dfe-9d57-17db1a2f0a74",
      "affectedData": [
        {
          "vendor": "The HDF Group",
          "product": "HDF5",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "<=2.3.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "0253b833-3e77-4dfe-9d57-17db1a2f0a74",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 6.9,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "PASSIVE",
          "vulnConfidentialityImpact": "LOW",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-06T14:29:51.698432Z",
          "id": "CVE-2026-19027",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "0253b833-3e77-4dfe-9d57-17db1a2f0a74",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/HDFGroup/hdf5/issues/6489",
      "source": "0253b833-3e77-4dfe-9d57-17db1a2f0a74"
    },
    {
      "url": "https://github.com/HDFGroup/hdf5/issues/6492",
      "source": "0253b833-3e77-4dfe-9d57-17db1a2f0a74"
    },
    {
      "url": "https://github.com/HDFGroup/hdf5/pull/6497",
      "source": "0253b833-3e77-4dfe-9d57-17db1a2f0a74"
    },
    {
      "url": "https://github.com/HDFGroup/hdf5/issues/6489",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}