CVE-2026-19027 (GCVE-0-2026-19027)

Vulnerability from cvelistv5 – Published: 2026-08-05 23:12 – Updated: 2026-08-06 14:30
VLAI
Title
HDF5 out-of-bounds heap read in N-Bit filter decompression
Summary
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.
Severity
6.9 (Medium)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-06 14:29 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
The HDF Group HDF5 Affected: <=2.3.0
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