HDF5 H5FL.c H5FL__reg_gc_list use after free
Priority MEDIUM 55CWE-119Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Deferred Red Hat: fix deferred
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
A vulnerability, which was classified as problematic, was found in HDF5 1.14.6. Affected is the function H5FL__reg_gc_list of the file src/H5FL.c. The manipulation leads to use after free. Attacking locally is a requirement. The exploit has been disclosed to the public and may be used.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00254 17th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD and the CNA
Fix Deferred Red Hat: fix deferred
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | HDF5 | 1.14.6 | — | No fix listed | CNA |
- HDF5 Vendor— Affected 1.14.6 Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:hdfgroup:hdf5:1.14.6:*:*:*:*:*:*:* | 1.14.6 | Vulnerable | The HDF Group |
- cpe:2.3:a:hdfgroup:hdf5:1.14.6:*:*:*:*:*:*:* Versions 1.14.6 Vulnerable ·The HDF Group
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux AI (RHEL AI) | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2025-6856
- 2026-10-03 Alias added: GHSA-wxfp-rw9f-g4g7
References
More The HDF Group Hdf5 vulnerabilities
- TI-2025-28698 hdf5 v1.14.6 was discovered to contain a heap buffer overflow via the H5Z__filter_scaleoffset function. CVSS 3.1HIGH 8.8
- TI-2025-28697 hdf5 v1.14.6 was discovered to contain a heap buffer overflow via the H5VM_memcpyvv function. CVSS 3.1HIGH 8.8
- TI-2020-13412 Buffer Overflow vulnerability in function H5S_close in H5S.c in HDF5 1.10.4 allows remote… CVSS 3.1HIGH 8.8
- TI-2021-15413 Buffer Overflow vulnerability in HDFGroup hdf5-h5dump 1.12.0 through 1.13.0 allows… CVSS 3.1HIGH 7.5
- TI-2026-26978 HDF5: H5T__conv_struct Use After Free CVSS 3.1HIGH 7.8
- TI-2022-09532 Heap-based buffer overflow in HDF Group libhdf5 CVSS 3.1HIGH 7.8
Sources
- CVE-2025-6856 · CVE Program
- CVE-2025-6856 · NVD
- FIRST EPSS
- GHSA-wxfp-rw9f-g4g7 · GitHub Advisory Database · CC BY 4.0
- CVE-2025-6856 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences