CVE-2016-4331 in HDF5
Summary
by MITRE
When decoding data out of a dataset encoded with the H5Z_NBIT decoding, the HDF5 1.8.16 library will fail to ensure that the precision is within the bounds of the size leading to arbitrary code execution.
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Analysis
by VulDB Data Team • 06/03/2019
The vulnerability identified as CVE-2016-4331 represents a critical security flaw within the HDF5 library version 1.8.16 that specifically affects the H5Z_NBIT decoding mechanism. This issue arises during the processing of datasets that have been encoded using the nbit filter, which is designed to handle data with non-standard bit precision requirements. The flaw manifests when the library attempts to decode data streams that contain malformed precision specifications, creating a scenario where the application fails to validate input parameters properly before executing operations that could lead to memory corruption.
The technical root cause of this vulnerability stems from inadequate bounds checking within the H5Z_NBIT decoding routine. When processing encoded data, the HDF5 library does not sufficiently validate that the specified precision values fall within acceptable ranges relative to the actual data size. This validation gap allows an attacker to craft malicious datasets with carefully constructed precision parameters that exceed the allocated memory boundaries. The flaw can be categorized under CWE-129 Input Validation and CWE-787 Out-of-bounds Write, as it enables both insufficient input validation and memory corruption through improper bounds checking.
The operational impact of CVE-2016-4331 extends beyond simple privilege escalation as it enables arbitrary code execution in the context of any application that utilizes the vulnerable HDF5 library. This means that any software system relying on HDF5 for data processing, including scientific computing platforms, data analysis tools, and file format handling applications, could become compromised when processing maliciously crafted HDF5 files. The vulnerability is particularly dangerous in environments where users can upload or process external data files, as it provides a direct path for remote code execution attacks. Attackers can exploit this flaw by creating specially formatted HDF5 datasets that, when opened or processed by vulnerable applications, trigger the memory corruption leading to arbitrary code execution.
Mitigation strategies for CVE-2016-4331 primarily involve upgrading to patched versions of the HDF5 library where the bounds checking has been properly implemented. Organizations should prioritize updating their systems to HDF5 versions 1.8.17 or later, which contain the necessary fixes for this vulnerability. Additionally, administrators should implement strict input validation measures for any data processing pipelines that handle HDF5 files, including sanitization of input parameters and monitoring for anomalous precision specifications. From an operational security perspective, the vulnerability aligns with ATT&CK technique T1059 Command and Scripting Interpreter, as the arbitrary code execution capability enables attackers to execute malicious payloads within the target environment. Network segmentation and file access controls should be implemented to limit the potential impact of exploitation, particularly in multi-tenant environments where untrusted data processing is common.