H5O__layout_decode in H5Olayout.c in HDF5 through 2.3.0 does not validate that a chunked dataset's stored chunk-layout dimensionality matches its dataspace rank when an existing dataset is opened, whereas this check is performed only at dataset-creation time. This allows attackers to cause a denial of service (divide-by-zero and application crash in H5S__hyper_iter_get_seq_list in src/H5Shyper.c) via a crafted HDF5 file with mismatched chunk/dataspace ranks that is opened and read via H5Dopen2 and H5Dread, e.g. by the h5repack tool.
Published: 2026-08-05
Updated: 2026-08-05
Base Score: 4.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 6.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Severity: Medium
Base Score: 6.8
Vector: 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
Severity: Medium