CVE-2019-15753: Openstack OS-Vif

Critical severity, CVSS 9.1. EPSS: 2.6% chance of exploitation in the next 30 days.

In OpenStack os-vif 1.15.x before 1.15.2, and 1.16.0, a hard-coded MAC aging time of 0 disables MAC learning in linuxbridge, forcing obligatory Ethernet flooding of non-local destinations, which both impedes network performance and allows users to possibly view the content of packets for instances belonging to other tenants sharing the same network. Only deployments using the linuxbridge backend are affected. This occurs in PyRoute2.add() in internal/command/ip/linux/impl_pyroute2.py.

Affected products

• Openstack OS-Vif: from 1.15.0, before 1.15.2 (fixed in 1.15.2); version 1.16.0 only

Published 2019-08-28. Last modified 2026-06-17.