CVE-2026-19025
Description
A flaw was found in HDF5. An attacker can craft a malicious HDF5 file that, when opened and read by an application, exploits a validation bypass. This bypass, related to mismatched chunk-layout dimensionality and dataspace rank, leads to a divide-by-zero error, causing a denial of service (DoS) and application crash.
Statement
A flaw was found in HDF5's H5O__layout_decode() function. When opening an existing dataset, HDF5 fails to validate that a chunked dataset's stored chunk-layout dimensionality matches its dataspace rank. An attacker can craft a malicious HDF5 file with mismatched dimensionality and trick a user or application into opening and reading it via functions like H5Dopen2() or utilities like h5repack. Processing this file triggers a divide-by-zero arithmetic exception in H5S__hyper_iter_get_seq_list(), resulting in an immediate application crash and denial of service.
Mitigation
Do not open or process untrusted HDF5 files using applications or utilities (such as h5repack) linked against vulnerable versions of the HDF5 library. Ensure files originate from trusted sources or isolate untrusted file parsing within a sandboxed environment.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
A Divide by Zero results in a crash.
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