High severity · published Feb 19, 2026
CVE-2026-26200
HDF5 Affected by H5T__conv_struct_opt Heap Buffer Overflow
7.8
CVSS
0.4%
EPSS
No
On KEV
Description
HDF5 is software for managing data. Prior to version 1.14.4-2, an attacker who can control an `h5` file parsed by HDF5 can trigger a write-based heap buffer overflow condition. This can lead to a denial-of-service condition, and potentially further issues such as remote code execution depending on the practical exploitability of the heap overflow against modern operating systems. Real-world exploitability of this issue in terms of remote-code execution is currently unknown. Version 1.14.4-2 fixes the issue.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HD
hdf5 · HDFGroup
< 1.14.4-2 · source: vendor, NVD
RH
Red Hat Enterprise Linux AI (RHEL AI) 3 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-26200
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-26200
Exploit
https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5p2m-j456-9mr2
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-26200
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2441088
security.access.redhat.com
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26200.json
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