# CVE-2026-86095: Unidata netcdf-c through 4.10.1 Out-of-bounds Write via Oversized HDF5 Attribute Name

> Attackers can cause memory corruption and crashes in applications using netcdf-c by providing crafted HDF5 files with oversized attribute names.

- **Severity:** High 8.5 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 4 Sep 2026
- **Updated:** 8 Sep 2026
- **Also known as:** AZL-99894, DEBIAN-CVE-2026-86095, ECHO-9fe9-af29-5ad7, GHSA-mm3m-jp7w-cj3m, SUSE-SU-2026:4249-1, UBUNTU-CVE-2026-86095

## What is CVE-2026-86095?

CVE-2026-86095 is a high-severity memory corruption vulnerability in Unidata netcdf-c, published on 4 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

Unidata netcdf-c through 4.10.1 contains an out-of-bounds write vulnerability in NC4_HDF5_inq_attname() that copies HDF5 attribute names into a fixed 256-byte buffer without length validation. Attackers can craft HDF5 files with oversized attribute names to overflow the destination buffer, causing memory corruption and crashes when applications enumerate attribute names.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-86095?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `netcdf` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf-openmpi2` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf-openmpi3` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf-openmpi4` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf_4_7_4-gnu-hpc` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf_4_7_4-gnu-mpich-hpc` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf_4_7_4-gnu-mvapich2-hpc` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf_4_7_4-gnu-openmpi2-hpc` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf_4_7_4-gnu-openmpi3-hpc` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |
| `netcdf_4_7_4-gnu-openmpi4-hpc` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 4.7.4-150600.15.5.1 |

## How do I fix CVE-2026-86095?

Apply the vendor's patch.

## Is CVE-2026-86095 being exploited?

There is no known exploitation of CVE-2026-86095 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-86095 and fix it if it is affected.

What it is: CVE-2026-86095 is a high-severity memory corruption vulnerability in Unidata netcdf-c, published on 4 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-86095 in the wild and no public exploit code.

Affected product: Unidata netcdf-c. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-86095/ (Markdown: https://insights.sbomify.com/CVE-2026-86095/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-86095
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-86095
- OSV: https://osv.dev/vulnerability/CVE-2026-86095

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-86095/
Summaries are generated and may contain mistakes; the official description above is the record.