High severity · published Aug 5, 2026
CVE-2026-19024
HDF5 H5Pget_fill_value NULL Pointer Dereference via Malformed Fill Value Message
8.2
CVSS
0.2%
EPSS
No
On KEV
Description
NULL pointer dereference in H5Pget_fill_value in HDF5 before 2.3.0 allows attackers to cause a denial of service via a dataset whose version 1 or 2 fill value message has the "defined" flag set together with a negative size field, which is not normalized to the library's "undefined" sentinel and reaches H5T_path_find with a NULL datatype.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HD
HDF5 · The HDF Group
<= 2.3.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-19024
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-19024
github.com
https://github.com/HDFGroup/hdf5/issues/6487
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