CVE-2026-50266: Low severity Openstack Neutron vulnerability
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 deviceowner to a value that has "network:" at the beginning ("network:dhcp" for example). The default port RBAC policies incorrectly included PROJECTMANAGER 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).
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
OpenStack Neutronto a version that resolves this vulnerability.Fixed in 28.0.1 - Compensating control
If you cannot upgrade to a version where Neutron has the corrected default port RBAC policies, restrict PROJECT_MANAGER privileges so project managers cannot create/update ports on shared networks without network ownership (the issue is that default port RBAC policies incorrectly included PROJECT_MANAGER without requiring network ownership).
Event History
Frequently Asked Questions
What is the severity of CVE-2026-50266?
The severity of CVE-2026-50266 is rated low, with a score of 2.2.
What is the risk associated with CVE-2026-50266?
CVE-2026-50266 has a risk rating of 13.
How do I fix CVE-2026-50266?
To fix CVE-2026-50266, upgrade OpenStack Neutron to version 28.0.1 or later.
What does CVE-2026-50266 exploit?
CVE-2026-50266 exploits the default port RBAC policies in OpenStack Neutron that allow project managers to manipulate shared network ports.
Who is affected by CVE-2026-50266?
CVE-2026-50266 primarily affects projects using OpenStack Neutron prior to version 28.0.1, allowing unauthorized modifications by project managers.