How severe is CVE-2025-6856?

CVE-2025-6856 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2025-6856 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-6856?

CVE-2025-6856 affects Hdfgroup Hdf5. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-6856?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-6856 have an EU (EUVD) identifier?

Yes. CVE-2025-6856 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19481.

When was CVE-2025-6856 published?

CVE-2025-6856 was published on 2025-06-29 and last updated on 2026-06-17.

CVE-2025-6856

CVE-2025-6856 is a low-severity vulnerability in Hdfgroup Hdf5 with a CVSS 3.x base score of 3.3. 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-119.

Key facts

Severity: Low (CVSS 3.x base score 3.3)
CVSS v2: 1.7
CVSS v4: 1.9
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-19481
Weakness: CWE-119
Affected product: Hdfgroup Hdf5
Published: 2025-06-29
Last modified: 2026-06-17

Description

A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.

Frequently asked questions

What is CVE-2025-6856?: A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
How severe is CVE-2025-6856?: CVE-2025-6856 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2025-6856 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-6856?: CVE-2025-6856 affects Hdfgroup Hdf5. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-6856?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-6856 have an EU (EUVD) identifier?: Yes. CVE-2025-6856 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19481.
When was CVE-2025-6856 published?: CVE-2025-6856 was published on 2025-06-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:hdfgroup:hdf5:1.14.6:*:*:*:*:*:*:*

More vulnerabilities in Hdfgroup Hdf5

CVE-2024-32608 — Critical (CVSS 9.8): HDF5 library through 1.14.3 has memory corruption in H5A__close resulting in the corruption of the instruction pointer…
CVE-2024-33874 — Critical (CVSS 9.8): HDF5 Library through 1.14.3 has a heap buffer overflow in H5O__mtime_new_encode in H5Omtime.c.
CVE-2024-32621 — Critical (CVSS 9.8): HDF5 Library through 1.14.3 contains a heap-based buffer overflow in H5HG_read in H5HG.c (called from…
CVE-2024-32615 — Critical (CVSS 9.8): HDF5 Library through 1.14.3 contains a heap-based buffer overflow in H5Z__nbit_decompress_one_byte in H5Znbit.c, caused…
CVE-2024-32611 — Critical (CVSS 9.8): HDF5 Library through 1.14.3 may use an uninitialized value in H5A__attr_release_table in H5Aint.c.
CVE-2024-29164 — Critical (CVSS 9.8): HDF5 through 1.14.3 contains a stack buffer overflow in H5R__decode_heap, resulting in the corruption of the…

All CVEs affecting Hdfgroup Hdf5 →

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…
CVE-2025-1866 — Critical (CVSS 10.0): Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows…
CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.

Browse all CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities →