# CVE-2026-92627: HDF5 heap-use-after-free in floating-point datatype conversion

Source: https://junglewise.ai/threats/cve-2026-92627-hdf5-heap-use-after-free-in-floating-point-datatype-conversion  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-16. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-92627 · Severity: info · CVSS 7.5 · Published 2026-09-16

HDF5 is a widely-used library for managing large scientific datasets. A heap-use-after-free vulnerability in the floating-point conversion routine can be triggered when parsing a specially crafted HDF5 file containing a compound datatype. An attacker who can supply such a file can cause applications like h5dump to crash or, potentially, execute arbitrary code, affecting any service that processes untrusted HDF5 data.

## Quick answers

**Is CVE-2026-92627 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-92627 being exploited in the wild.

**How severe is CVE-2026-92627?** Informational severity, with a CVSS score of 7.5, published 16 September 2026.

**Which products and versions are affected?** HDF Group HDF5 before 1.14.2.

**Is there a fix for CVE-2026-92627?** 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-2026-92627 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-92627?** 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

The vulnerability is a heap-use-after-free in the H5T__conv_f_f() function in src/H5Tconv.c, triggered during conversion of compound datatypes containing floating-point members. A temporary buffer is allocated via calloc() during dataset read operations, then freed and subsequently read from within the same conversion routine. The attack vector requires the attacker to supply a malicious HDF5 file that will be parsed by an application using the affected HDF5 library (versions prior to 1.14.2). The immediate impact is denial of service through a crash; depending on heap layout and allocator behavior, exploitation for memory corruption or remote code execution may be possible. A patch is available in HDF5 version 1.14.2 and later.

## Affected products

- HDF Group HDF5 before 1.14.2

## Timeline

- 2026-09-16: disclosed
- 2024-09-20: advisory: Pulse Security advisory published with PoC and fuzzing details

## References

- [https://pulsesecurity.co.nz/advisories/hdf5-memory-corruption](https://pulsesecurity.co.nz/advisories/hdf5-memory-corruption)