A vulnerability within the Endpoint Learning feature of Cisco Nexus 9000 Series Switches running in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an endpoint device in certain circumstances. The vulnerability is due to improper endpoint learning when packets are received on a specific port from outside the ACI fabric and destined to an endpoint located on a border leaf when Disable Remote Endpoint Learning has been enabled. This can result in a Remote (XR) entry being created for the impacted endpoint that will become stale if the endpoint migrates to a different port or leaf switch. This results in traffic not reaching the impacted endpoint until the Remote entry can be relearned by another mechanism.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Nx-os | Cisco | 12.3(1h) (including) | 12.3(1h) (including) |
| Nx-os | Cisco | 13.1(2m) (including) | 13.1(2m) (including) |
| Nx-os | Cisco | 13.1(2o) (including) | 13.1(2o) (including) |
| Nx-os | Cisco | 13.1(2p) (including) | 13.1(2p) (including) |