CVE-2026-19027

The H5Z__nbit_decompress_one_byte, H5Z__nbit_decompress_one_nooptype, and H5Z__nbit_decompress_one_atomic functions in H5Znbit.c in HDF5 through 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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/HDFGroup/hdf5/issues/6489
https://github.com/HDFGroup/hdf5/issues/6492
https://github.com/HDFGroup/hdf5/pull/6497
https://github.com/HDFGroup/hdf5/issues/6489

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-06 00:16

Updated : 2026-08-31 19:23

NVD link : CVE-2026-19027

Mitre link : CVE-2026-19027

CVE.ORG link : CVE-2026-19027

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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