Vulnerability · Published Aug 5, 2026 · Assigned by HDFG
CVE-2026-19025HDF5 divide-by-zero (SIGFPE) via mismatched chunk-layout dimensionality and dataspace rank on dataset open
Medium 6.8
In plain English
A medium-severity security flaw in HDF5 from The HDF Group. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities).
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | hdf5 | no fix listed | DEBIAN-CVE-2026-19025 |
| Debian:13 | hdf5 | no fix listed | DEBIAN-CVE-2026-19025 |
| Debian:14 | hdf5 | no fix listed | DEBIAN-CVE-2026-19025 |
| Ubuntu:22.04:LTS | hdf5 | no fix listed | UBUNTU-CVE-2026-19025 |
| Ubuntu:24.04:LTS | hdf5 | no fix listed | UBUNTU-CVE-2026-19025 |
| Ubuntu:26.04:LTS | hdf5 | no fix listed | UBUNTU-CVE-2026-19025 |
| Ubuntu:26.10 | hdf5 | no fix listed | UBUNTU-CVE-2026-19025 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| The HDF Group | HDF5 | <= 2.3.0 |
Weakness: CWE-369 · 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