# CVE-2026-17572: The HDF Group HDF5 heap buffer overflow in SOHM list-index deserialization

Source: https://junglewise.ai/threats/cve-2026-17572-the-hdf-group-hdf5-heap-buffer-overflow-in-sohm-list-index  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-27. Updated: 2026-07-27  
License: CC BY 4.0 with a link back

CVE-2026-17572 · Severity: info · CVSS 5.5 · Published 2026-07-27

HDF5 is a widely used data management library for storing and managing large amounts of complex data. A vulnerability in how the library processes certain file structures allows an attacker to crash applications that open a specially crafted, malicious HDF5 file. This could lead to a denial of service, impacting operations that rely on processing external data files.

## Quick answers

**Is CVE-2026-17572 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-17572 being exploited in the wild.

**How severe is CVE-2026-17572?** Informational severity, with a CVSS score of 5.5, published 27 July 2026.

**Which products and versions are affected?** The HDF Group HDF5 <= 2.1.1.

**Is there a fix for CVE-2026-17572?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-17572 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-17572?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A heap-based buffer overflow exists in the Shared Object Header Message (SOHM) list-index deserialization component of HDF5. The vulnerability is located in the H5SM__cache_list_deserialize and H5SM__cache_list_verify_chksum functions, which fail to validate that the 'num_messages' count from the on-disk index header does not exceed 'list_max'. An attacker can provide a malformed HDF5 file that triggers out-of-bounds heap reads and writes. This requires a user to open the malicious file (User Interaction). The issue affects HDF5 through version 2.1.1 across all platforms.

## Affected products

- The HDF Group HDF5 <= 2.1.1

## Timeline

- 2026-07-02: disclosed: Issue reported on GitHub
- 2026-07-27: advisory: NVD publication date

## References

- [https://github.com/HDFGroup/hdf5/issues/6501](https://github.com/HDFGroup/hdf5/issues/6501)