CVE-2026-86095: Out-of-bounds Write in Unidata netcdf-c
Description
Unidata netcdf-c versions up to 4.10.1 have an out-of-bounds write vulnerability in the NC4_HDF5_inq_attname() function. This occurs because HDF5 attribute names are copied into a fixed 256-byte buffer without length validation. Crafted HDF5 files with oversized attribute names can cause buffer overflow, leading to memory corruption and application crashes during attribute enumeration. The vulnerability has a high severity with a CVSS score of 8.5.
CVSS v4.0
Score 8.5high
Affected software
Unidata
netcdf-c
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-86095 is an out-of-bounds write vulnerability in Unidata netcdf-c (<=4.10.1) within the NC4_HDF5_inq_attname() function. The flaw arises from copying HDF5 attribute names into a fixed-size 256-byte buffer without validating the attribute name length. Maliciously crafted HDF5 files containing attribute names exceeding this buffer size can trigger a buffer overflow, resulting in memory corruption and potential application crashes during attribute enumeration.
Potential Impact
Exploitation of this vulnerability can lead to memory corruption and application crashes when processing maliciously crafted HDF5 files with oversized attribute names. This may affect the stability and reliability of applications using vulnerable netcdf-c versions. There is no indication of privilege escalation or remote code execution in the provided data.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, avoid processing untrusted or malformed HDF5 files with oversized attribute names to mitigate risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-04T22:17:23.895Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a9b4bc3acd9273b49619dd3
Added to database: 09/04/2026, 22:52:51 UTC
Last enriched: 10/17/2026, 23:25:42 UTC
Last updated: 10/18/2026, 06:48:20 UTC
Views: 112
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