Medium severity · published Aug 5, 2026
CVE-2026-19023
HDF5 h5dump Untrusted Pointer Dereference in Binary Output of Variable-Length String Datasets
6.8
CVSS
0.2%
EPSS
No
On KEV
Description
Untrusted pointer dereference in the render_bin_output function in the h5dump tool in HDF5 before 2.3.0 allows attackers to cause a denial of service via a variable-length string dataset with more than one element dumped in binary mode, which corrupts the per-element stride calculation and causes subsequent elements to be read from a misaligned offset and dereferenced as a pointer.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% 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-2026-19023
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-19023
github.com
https://github.com/HDFGroup/hdf5/issues/6486
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