Is CVE-2026-26200 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-26200 being exploited in the wild.

How severe is CVE-2026-26200?

High severity, with a CVSS score of 7.8, published 19 February 2026.

Which products and versions are affected?

Red Hat Enterprise Linux AI (RHEL AI) 3 affected.

Is there a fix for CVE-2026-26200?

A patch was published on 2026-02-19: Version 1.14.4-2 released to fix the issue Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-26200 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-26200?

Check whether you run Hdfgroup Hdf5 or Red Hat Enterprise Linux AI (RHEL AI) 3 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-26200: HDFGroup HDF5 heap buffer overflow in H5T__conv_struct_opt

CVE-2026-26200 · Severity: high · CVSS 7.8 · Published 2026-02-19

HDF5 is a widely used library and file format for managing and storing large amounts of complex data. A security vulnerability has been identified where a specially crafted data file (.h5) can cause the software to crash or potentially allow an attacker to run unauthorized code. This risk is primarily present when a user is tricked into opening a malicious file or if an automated system processes untrusted data.

Technologies: Hdfgroup Hdf5, Red Hat Enterprise Linux AI (RHEL AI) 3. Vendors: Hdfgroup, Red Hat.

Quick answers

Is CVE-2026-26200 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-26200 being exploited in the wild.
How severe is CVE-2026-26200?: High severity, with a CVSS score of 7.8, published 19 February 2026.
Which products and versions are affected?: Red Hat Enterprise Linux AI (RHEL AI) 3 affected.
Is there a fix for CVE-2026-26200?: A patch was published on 2026-02-19: Version 1.14.4-2 released to fix the issue Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-26200 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-26200?: Check whether you run Hdfgroup Hdf5 or Red Hat Enterprise Linux AI (RHEL AI) 3 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A heap-based buffer overflow exists in HDF5 due to an incorrect calculation of buffer size in the H5T__conv_struct_opt method. The vulnerability is triggered when the library parses a maliciously crafted .h5 file, specifically through the h5dump utility or other components using the H5T conversion functions. An attacker can achieve an out-of-bounds write, leading to a denial-of-service (crash) or potentially arbitrary code execution. While the primary attack vector involves local user interaction (opening a file), server-side processes that automatically parse user-supplied HDF5 files are also at risk. The issue is addressed in version 1.14.4-2.

Affected products

HDFGroup HDF5 < 1.14.4-2
Red Hat Red Hat Enterprise Linux AI (RHEL AI) 3 affected

Timeline

2026-02-14: advisory: GitHub advisory published by HDFGroup
2026-02-19: disclosed: CVE-2026-26200 published
2026-02-19: patched: Version 1.14.4-2 released to fix the issue

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.