# CVE-2026-50266: OpenStack Neutron: Neutron port RBAC policy bypass allows project managers to set trusted device owners on shared networks

> Project managers can spoof network services on shared networks due to incorrect RBAC policies, bypassing security protections against other tenants.

- **Severity:** Low 2.2 (`CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Jun 2026
- **Updated:** 4 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-50266, GHSA-qmc5-gv6v-8p22, PYSEC-2026-3491, UBUNTU-CVE-2026-50266

## What is CVE-2026-50266?

CVE-2026-50266 is a low-severity missing authorization vulnerability in OpenStack Neutron, published on 4 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

In OpenStack Neutron before 28.0.1, a project manager can create or update a port on a shared network owned by another project and set device_owner to a value that has "network:" at the beginning ("network:dhcp" for example). The default port RBAC policies incorrectly included PROJECT_MANAGER without requiring network ownership, allowing any project manager to obtain trusted network-service port behavior on shared networks. Depending on backend and deployment, this can bypass anti-spoofing and security group protections, enabling DHCP, MAC, or IP spoofing against other tenants on the shared network. This is a regression of CVE-2015-5240 (OSSA-2015-018).

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-50266?

3 open source packages ship an affected version, including neutron.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `neutron` | PyPI | All versions | 28.0.1 |
| `neutron` | PyPI | All versions | 28.0.1 |
| `neutron` | PyPI | All versions | 28.0.1 |

## How do I fix CVE-2026-50266?

Upgrade neutron to 28.0.1 or later.

## Is CVE-2026-50266 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-50266 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-50266 and fix it if it is affected.

What it is: CVE-2026-50266 is a low-severity missing authorization vulnerability in OpenStack Neutron, published on 4 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-50266 exists.

Affected packages and fixed versions:
- neutron (PyPI): affected all versions; fixed in 28.0.1
- neutron (PyPI): affected all versions; fixed in 28.0.1
- neutron (PyPI): affected all versions; fixed in 28.0.1

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-2026-50266/ (Markdown: https://insights.sbomify.com/CVE-2026-50266/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-50266
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-50266
- OSV: https://osv.dev/vulnerability/CVE-2026-50266

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-50266/
Summaries are generated and may contain mistakes; the official description above is the record.