# CVE-2026-79619: OpenZFS: user-namespace capability check allows unprivileged local authorization bypass

> Unprivileged local users can bypass authorization checks in OpenZFS via user namespaces to perform administrative pool operations and fault injection.

- **Severity:** High 7.3 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-79619, ECHO-a835-6f03-ef3a, GHSA-5v2p-vxxv-r62r, GHSA-mhf5-q8gw-qg9v, UBUNTU-CVE-2026-79619, USN-8705-1, USN-8705-2

## What is CVE-2026-79619?

CVE-2026-79619 is a high-severity authentication bypass vulnerability in OpenZFS, published on 26 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

On Linux, several OpenZFS ioctl authorization checks accept a capability held only within a user-created, unprivileged namespace as equivalent to real host privilege, allowing an unprivileged local user to perform operations that should require root. Affected operations include pool-administrative operations (eg create, import, destroy), pool event log access (zpool events) and fault injection (zinject). Exploiting the problem requires only that the local user is permitted to open /dev/zfs (governed by local device permissions) and that the kernel permits unprivileged user namespace creation. No prior access to the target pool or its underlying devices is needed.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-79619?


## How do I fix CVE-2026-79619?

Apply the vendor's patch.

## Is CVE-2026-79619 being exploited?

There is no known exploitation of CVE-2026-79619 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-79619 and fix it if it is affected.

What it is: CVE-2026-79619 is a high-severity authentication bypass vulnerability in OpenZFS, published on 26 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-79619 in the wild and no public exploit code.

Affected product: OpenZFS. 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-2026-79619/ (Markdown: https://insights.sbomify.com/CVE-2026-79619/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-79619
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-79619
- OSV: https://osv.dev/vulnerability/CVE-2026-79619

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-79619/
Summaries are generated and may contain mistakes; the official description above is the record.