CVE-2025-2925 is a medium-severity vulnerability identified in the HDF5 library, versions up to and including 1.14.6. The flaw exists in the function H5MM_realloc within the source file src/H5MM.c, where improper handling of the memory argument 'mem' can lead to a double free condition. A double free occurs when the same memory location is freed more than once, which can corrupt the memory management data structures, potentially leading to undefined behavior such as application crashes or, in some cases, arbitrary code execution. The vulnerability requires local access with low privileges (PR:L) and does not require user interaction or authentication. The attack vector is local, meaning an attacker must have some level of access to the system to exploit this flaw. The CVSS 4.0 base score is 4.8, reflecting a medium severity level, with partial impact on availability and integrity but no impact on confidentiality. Although the exploit has been publicly disclosed, there are no known exploits actively used in the wild at this time. The vulnerability affects all HDF5 versions from 1.14.0 through 1.14.6, which are widely used in scientific computing, data analysis, and engineering applications for managing large and complex data sets in hierarchical data formats. Because HDF5 is often embedded in larger software stacks or used in research and industrial environments, the vulnerability could be leveraged by a local attacker to disrupt services or cause denial of service conditions, potentially impacting critical data processing workflows.

For European organizations, the impact of CVE-2025-2925 depends largely on the extent to which HDF5 is integrated into their software environments. Industries such as scientific research institutions, engineering firms, aerospace, automotive, and manufacturing sectors frequently use HDF5 for handling large datasets. A successful exploitation could lead to application crashes or data integrity issues, disrupting critical data analysis and operational processes. While the vulnerability does not directly expose confidential data, the potential for denial of service or integrity compromise could affect research outputs, production quality, or operational reliability. Given the local attack vector, the threat is more significant in environments where multiple users have local access or where attackers can gain initial footholds through other means. European organizations relying on HPC clusters, research labs, or industrial control systems that incorporate HDF5 should be particularly cautious. The absence of known active exploits reduces immediate risk but does not eliminate the threat, especially as public exploit details may facilitate future attacks.

To mitigate CVE-2025-2925, European organizations should prioritize upgrading to a patched version of HDF5 once available, or apply vendor-supplied patches promptly. In the interim, restrict local access to systems running vulnerable HDF5 versions by enforcing strict user permissions and employing robust access controls. Implement monitoring to detect abnormal application crashes or memory corruption signs that could indicate exploitation attempts. For environments where HDF5 is embedded in larger software stacks, coordinate with software vendors to ensure updated components are deployed. Additionally, conduct regular audits of local user accounts and privilege levels to minimize the risk of local exploitation. Employ application whitelisting and endpoint protection solutions capable of detecting anomalous behavior related to memory corruption. Finally, educate system administrators and users about the risks of local exploitation and the importance of maintaining updated software components.