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).
Exploitability
AV:NAC:HPR:HUI:NScope
S:UImpact
C:NI:LA:N2.2/CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:NAccess Control