# CVE-2026-73439: Security Advisory 0164

> Authenticated users may bypass gNSI Pathz restrictions to read or write gNMI paths when specific group and user rules conflict.

- **Severity:** High 7.7 (`CVSS:4.0/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 16 Sep 2026
- **Updated:** 17 Sep 2026
- **Also known as:** GHSA-hhmm-qmjm-g2hp

## What is CVE-2026-73439?

CVE-2026-73439 is a high-severity missing authorization vulnerability in Arista Networks EOS, published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

On affected platforms running Arista EOS, if OpenConfig is configured and running a gNMI server on the system, and if gNSI Pathz is configured and a gNSI Pathz policy is present on the system, then gNMI may fail to correctly enforce the rules in this policy if both a group rule and a user rule for the same path is present in the policy. Under certain conditions, this can lead to an authenticated user gaining unauthorized permission to read or write gNMI paths that the Pathz policy is intended to restrict.

Weakness: CWE-842 (Placement of User into Incorrect Group)

## Which versions are affected by CVE-2026-73439?


## How do I fix CVE-2026-73439?

No fix has been published for CVE-2026-73439 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-73439 being exploited?

There is no known exploitation of CVE-2026-73439 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73439 and fix it if it is affected.

What it is: CVE-2026-73439 is a high-severity missing authorization vulnerability in Arista Networks EOS, published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-73439 in the wild and no public exploit code.

Affected product: Arista Networks EOS. 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-2026-73439/ (Markdown: https://insights.sbomify.com/CVE-2026-73439/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73439
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73439
- OSV: https://osv.dev/vulnerability/CVE-2026-73439

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73439/
Summaries are generated and may contain mistakes; the official description above is the record.