OpenStack os-vif Vulnerability: MAC Learning Bypass and Packet Viewing in Linuxbridge

OpenStack os-vif Vulnerability: MAC Learning Bypass and Packet Viewing in Linuxbridge

CVE-2019-15753 · MEDIUM Severity

AV:N/AC:L/AU:N/C:P/I:N/A:P

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.

Learn more about our Cis Benchmark Audit For Distribution Independent Linux.