How severe is CVE-2026-26200?

CVE-2026-26200 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-26200 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-26200?

CVE-2026-26200 affects Hdfgroup Hdf5. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-26200?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-26200 have an EU (EUVD) identifier?

Yes. CVE-2026-26200 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7979.

When was CVE-2026-26200 published?

CVE-2026-26200 was published on 2026-02-19 and last updated on 2026-06-30.

CVE-2026-26200

CVE-2026-26200 is a high-severity vulnerability in Hdfgroup Hdf5 with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-122.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7979
Weakness: CWE-122
Affected product: Hdfgroup Hdf5
Published: 2026-02-19
Last modified: 2026-06-30

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.

Frequently asked questions

What is CVE-2026-26200?: 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.
How severe is CVE-2026-26200?: CVE-2026-26200 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-26200 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-26200?: CVE-2026-26200 affects Hdfgroup Hdf5. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-26200?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-26200 have an EU (EUVD) identifier?: Yes. CVE-2026-26200 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7979.
When was CVE-2026-26200 published?: CVE-2026-26200 was published on 2026-02-19 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:hdfgroup:hdf5:*:*:*:*:*:*:*:*

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