CVE-2026-19028

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/HDFGroup/hdf5/issues/6488
https://github.com/HDFGroup/hdf5/issues/6490
https://github.com/HDFGroup/hdf5/pull/6497
https://github.com/HDFGroup/hdf5/issues/6488

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-06 00:16

Updated : 2026-08-31 19:23

NVD link : CVE-2026-19028

Mitre link : CVE-2026-19028

CVE.ORG link : CVE-2026-19028

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

CWE-190

Integer Overflow or Wraparound

CWE-1284

Improper Validation of Specified Quantity in Input

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