Vulnerability-Lookup

GHSA-2HG9-348W-39GJ

Vulnerability from github – Published: 2026-08-06 00:31 – Updated: 2026-08-06 00:31

Details

H5Z__filter_fletcher32 in H5Zfletcher32.c in HDF5 through 2.3.0 computes the data length to checksum by subtracting the 4-byte trailing checksum size from the input buffer size without checking that the buffer is at least 4 bytes, allowing a size_t underflow. This allows attackers to cause a denial of service (massively out-of-bounds read and application crash in H5_checksum_fletcher32) via a crafted HDF5 file with a Fletcher32-filtered chunk smaller than 4 bytes, triggered via H5Dread, e.g. by the h5ls or h5dump tools.

Severity

6.8 (Medium)


                  
                    CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-19028"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-06T00:16:53Z",
    "severity": "MODERATE"
  },
  "details": "H5Z__filter_fletcher32 in H5Zfletcher32.c in HDF5 through 2.3.0 computes the data length to checksum by subtracting the 4-byte trailing checksum size from the input buffer size without checking that the buffer is at least 4 bytes, allowing a size_t underflow. This allows attackers to cause a denial of service (massively out-of-bounds read and application crash in H5_checksum_fletcher32) via a crafted HDF5 file with a Fletcher32-filtered chunk smaller than 4 bytes, triggered via H5Dread, e.g. by the h5ls or h5dump tools.",
  "id": "GHSA-2hg9-348w-39gj",
  "modified": "2026-08-06T00:31:31Z",
  "published": "2026-08-06T00:31:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19028"
    },
    {
      "type": "WEB",
      "url": "https://github.com/HDFGroup/hdf5/issues/6488"
    },
    {
      "type": "WEB",
      "url": "https://github.com/HDFGroup/hdf5/issues/6490"
    },
    {
      "type": "WEB",
      "url": "https://github.com/HDFGroup/hdf5/pull/6497"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-19028 (GCVE-0-2026-19028)

Vulnerability from cvelistv5 – Published: 2026-08-05 23:15 – Updated: 2026-08-06 14:25

Title

HDF5 integer underflow in Fletcher32 filter leads to massive out-of-bounds read

Summary

Severity

6.8 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-06 14:24 UTC

CWE

CWE-190 - Integer overflow or wraparound
CWE-125 - Out-of-bounds read
CWE-1284 - Improper validation of specified quantity in input

Assigner

HDFG

References

3 references

URL	Tags
https://github.com/HDFGroup/hdf5/pull/6497
https://github.com/HDFGroup/hdf5/issues/6488
https://github.com/HDFGroup/hdf5/issues/6490

Impacted products

1 product

Vendor	Product	Version
The HDF Group	HDF5	Affected: <=2.3.0

Show details on NVD website

JSON

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                "id": "CVE-2026-19028",
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                    "Exploitation": "poc"
                  },
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                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-06T14:24:48.048981Z",
                "version": "2.0.3"
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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.

Detection rules are retrieved from Rulezet.

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.

Action not permitted

GHSA-2HG9-348W-39GJ

CVE-2026-19028 (GCVE-0-2026-19028)

Tags

Sightings

Nomenclature