CVE-2025-6818 in HDF5
Summary
by MITRE • 06/28/2025
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5O__chunk_protect of the file /src/H5Ochunk.c. The manipulation leads to heap-based buffer overflow. An attack has to be approached locally. The exploit has been disclosed to the public and may be used.
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Analysis
by VulDB Data Team • 06/30/2025
The vulnerability identified as CVE-2025-6818 represents a critical heap-based buffer overflow in the HDF5 library version 1.14.6, specifically within the H5O__chunk_protect function located in the /src/H5Ochunk.c source file. This flaw constitutes a serious security concern as it allows for potential memory corruption that could be exploited to execute arbitrary code or cause application crashes. The vulnerability's classification as problematic indicates the severity of impact on system integrity and data security. The buffer overflow occurs when the function processes chunked data structures within the HDF5 file format, which is widely used for storing and managing large scientific datasets across various domains including climate modeling, genomics, and computational physics.
The technical nature of this vulnerability stems from improper bounds checking within the H5O__chunk_protect function, which handles the protection of chunked object data in HDF5 files. When processing malformed or specially crafted HDF5 files containing malicious chunk data, the function fails to validate the size parameters of buffer allocations, leading to memory corruption beyond the intended buffer boundaries. This heap-based overflow creates opportunities for attackers to overwrite adjacent memory regions, potentially corrupting critical data structures or executing malicious code. The vulnerability's local attack requirement means that exploitation typically necessitates access to the target system, though the impact remains severe as it could affect any application or service utilizing the vulnerable HDF5 library. The public disclosure of exploit details significantly increases the risk to systems that have not yet implemented proper mitigations.
The operational impact of CVE-2025-6818 extends across multiple sectors that rely on HDF5 for data management, particularly in scientific computing environments where large datasets are common. Organizations using applications built on HDF5 libraries such as MATLAB, Python's h5py, or custom scientific software may face potential system compromise, data corruption, or denial of service conditions. The vulnerability affects not only individual applications but also the underlying data infrastructure that depends on HDF5's chunked storage mechanisms. Given the widespread adoption of HDF5 in research institutions, government agencies, and commercial entities, the potential for cascading effects across interconnected systems is significant. The exploit's public availability means that threat actors can readily leverage this vulnerability without requiring advanced technical skills or specialized knowledge.
Mitigation strategies for CVE-2025-6818 should prioritize immediate patching of all affected systems running HDF5 1.14.6, with organizations implementing comprehensive vulnerability management processes to identify and remediate similar issues across their software ecosystems. System administrators should conduct thorough inventory assessments to identify all applications and services utilizing the vulnerable HDF5 library, followed by coordinated patch deployment and testing procedures. Additional protective measures include implementing strict file validation protocols for HDF5 input data, deploying runtime monitoring systems to detect anomalous memory access patterns, and establishing network segmentation to limit potential lateral movement if exploitation occurs. The vulnerability aligns with CWE-121 heap-based buffer overflow categories and could be mapped to ATT&CK technique T1059.007 for execution through command and scripting interpreters, though the local attack vector limits its remote exploitation potential. Organizations should also consider implementing application whitelisting policies and privilege separation mechanisms to reduce the attack surface and limit the potential impact of successful exploitation attempts.