CVE-2025-6816 HDF5 H5Ofsinfo.c H5O__fsinfo_encode heap-based overflow

Medium 4.8 Published 28 Jun 2025 Updated 30 Jun 2025

A heap-based buffer overflow in the HDF5 library allows local attackers to execute arbitrary code or cause a denial of service.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2025-6816?

CVE-2025-6816 is a medium-severity memory corruption vulnerability in Hdfgroup Hdf5, published on 28 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A vulnerability classified as problematic was found in HDF5 1.14.6. This vulnerability affects the function H5O__fsinfo_encode of the file /src/H5Ofsinfo.c. The manipulation leads to heap-based buffer overflow. It is possible to launch the attack on the local host. The exploit has been disclosed to the public and may be used.

Weakness: CWE-122, CWE-119

Which versions are affected by CVE-2025-6816?

It affects 1 product.

Products include Hdfgroup Hdf5.

How do I fix CVE-2025-6816?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2025-6816 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-6816 exists.

All Hdfgroup Hdf5 vulnerabilities

Sources

Also known as AZL-64413, AZL-64437, DEBIAN-CVE-2025-6816, ECHO-0e95-bad6-f6e2, GHSA-x887-jv9q-xhvq, JLSEC-2026-343 and 1 more.