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.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
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
Which versions are affected by CVE-2026-50266?
3 open source packages ship an affected version, including neutron.
| Package | 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.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-50266 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-50266 exists.
Sources
Also known as DEBIAN-CVE-2026-50266, GHSA-qmc5-gv6v-8p22, PYSEC-2026-3491, UBUNTU-CVE-2026-50266.