CVE-2026-26199

HDF5 is a high-performance library and a file format specification that implements the HDF5 data model. If `H5Iget_name` is invoked on a group id with `0` for the size parameter, it will underflow when trying to place a null terminator in the buffer. This can occur if `H5Iget_name` is invoked in a way where `size` can be forced to zero, and there is important data before the `name` buffer.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/HDFGroup/hdf5/blob/develop/src/H5Gname.c#L474	Exploit
https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc	Vendor Advisory
https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:hdfgroup:hdf5:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-20 16:16

Updated : 2026-07-29 15:38

NVD link : CVE-2026-26199

Mitre link : CVE-2026-26199

CVE.ORG link : CVE-2026-26199

JSON object : View

Products Affected

hdfgroup

hdf5

CWE

CWE-124

Buffer Underwrite ('Buffer Underflow')

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