CVE-2025-44904 is a high-severity heap buffer overflow vulnerability identified in the HDF5 library version 1.14.6. The flaw exists in the H5VM_memcpyvv function, which is responsible for copying memory in a vectorized manner. A heap buffer overflow occurs when the function writes more data to a heap-allocated buffer than it can hold, potentially overwriting adjacent memory. This can lead to arbitrary code execution, data corruption, or application crashes. The vulnerability is exploitable remotely without privileges (AV:N/PR:N), but requires user interaction (UI:R), such as opening a maliciously crafted HDF5 file. The impact affects confidentiality, integrity, and availability (C:H/I:H/A:H), making it a critical concern for applications relying on HDF5 for scientific data storage and processing. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability is classified under CWE-122 (Heap-based Buffer Overflow), a common and dangerous memory corruption issue. Given the widespread use of HDF5 in scientific computing, data analytics, and engineering fields, this vulnerability poses a significant risk to systems processing untrusted HDF5 files.

European organizations involved in scientific research, engineering, and data analytics are at risk due to the extensive use of HDF5 for managing large and complex datasets. Exploitation could lead to unauthorized data disclosure, manipulation of critical scientific data, or disruption of research operations. The vulnerability could be leveraged to execute arbitrary code, potentially allowing attackers to establish persistence, move laterally, or exfiltrate sensitive information. Industries such as aerospace, automotive, pharmaceuticals, and academia, which heavily rely on HDF5 for simulation and experimental data, may face operational downtime and reputational damage. Furthermore, critical infrastructure entities using HDF5 for monitoring or control data could experience availability issues, impacting service continuity. The requirement for user interaction limits automated exploitation but does not eliminate risk, especially in environments where users routinely handle external data files.

Organizations should immediately audit their use of HDF5 libraries and identify systems running version 1.14.6. Until an official patch is released, it is advisable to restrict the processing of untrusted HDF5 files, especially from external or unknown sources. Implement strict file validation and sandboxing techniques to isolate the processing environment. Employ application whitelisting and behavior monitoring to detect anomalous activities indicative of exploitation attempts. Security teams should update incident response plans to include scenarios involving HDF5 exploitation. Additionally, consider deploying network-level controls to limit exposure and educate users about the risks of opening unverified HDF5 files. Once patches become available, prioritize timely application and verify the integrity of updates. For critical systems, consider temporary mitigation by disabling or replacing vulnerable HDF5-dependent components if feasible.