CVE-2019-1977

published 2019-08-30

CVE-2019-1977: A vulnerability within the Endpoint Learning feature of Cisco Nexus 9000 Series Switches running in Application Centric Infrastructure (ACI) mode could allow…

Priority P3 42 high 7.5 CVSS 3.0

AV N AC L PR N UI N S U C N I N A H

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

6 ranges

Vendor	Product	Version range	Fixed in
cisco	cisco_nexus_9000_series_fabric_switches_in_aci	>= unspecified < 12.2(4M)	12.2(4M)
cisco	nexus_9000_series_fabric_switches_aci_mode_border_leaf_endpoint_learning	—	—
cisco	nx-os	—	—
cisco	nx-os	—	—
cisco	nx-os	—	—
cisco	nx-os	—	—

CVSS provenance

nvd v3.0 7.5 HIGH CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd v2.0 4.3 MEDIUM AV:N/AC:M/Au:N/C:N/I:N/A:P

vendor_cisco 6.8 MEDIUM

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