Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV N H P N A N N H 5.9 .0026 17.4 —
AFFECTED Product Versions Fixed hdf5 <= 1.14.6 – —
TIMELINE Feb 11 Reserved by GitHub_M Jul 20 EXPLOIT PUBLISHED — CVE-2026-26199 (HDFGroup hdf5). Public exploit reference added. Jul 20 Published (CNA: GitHub_M)
HDF5 is a high-performance library and a file format specification that implements the HDF5 data model. If `H5Iget_name` is invoked on a group id with `0` for the size parameter, it will underflow when trying to place a null terminator in the buffer. This can occur if `H5Iget_name` is invoked in a way where `size` can be forced to zero, and there is important data before the `name` buffer.
| Date | Event | Detail |
|---|---|---|
| February 11, 2026 | Reserved | Reserved by GitHub_M |
| July 20, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-26199 (HDFGroup hdf5). Public exploit reference added. |
| July 20, 2026 | Published | Published (CNA: GitHub_M) |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| HDFGroup | hdf5 | — | <= 1.14.6 | — |
Authoritative record: CVE-2026-26199 at cve.org
Vendors: hdfgroup
Weaknesses: CWE-124
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-26199 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.