CVE-2019-1890: A vulnerability in the fabric infrastructure VLAN connection establishment of the Cisco Nexus 9000 Series Application Centric Infrastructure (ACI) Mode Switch…

PriorityP432medium6.5CVSS 3.1

AVAACLPRNUINSUCNIHAN

EPSS

0.63%

46.7th percentile

A vulnerability in the fabric infrastructure VLAN connection establishment of the Cisco Nexus 9000 Series Application Centric Infrastructure (ACI) Mode Switch Software could allow an unauthenticated, adjacent attacker to bypass security validations and connect an unauthorized server to the infrastructure VLAN. The vulnerability is due to insufficient security requirements during the Link Layer Discovery Protocol (LLDP) setup phase of the infrastructure VLAN. An attacker could exploit this vulnerability by sending a malicious LLDP packet on the adjacent subnet to the Cisco Nexus 9000 Series Switch in ACI mode. A successful exploit could allow the attacker to connect an unauthorized server to the infrastructure VLAN, which is highly privileged. With a connection to the infrastructure VLAN, the attacker can make unauthorized connections to Cisco Application Policy Infrastructure Controller (APIC) services or join other host endpoints.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
cisco	application_policy_infrastructure_controller	—	—
cisco	cisco_nx-os_system_software_in_aci_mode_11.0.1b	>= unspecified < 14.1(2g)	14.1(2g)
cisco	nexus_9000_series_fabric_switches_aci_mode_fabric_infrastructure_vlan_unauthoriz	—	—

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

nvdv3.07.4HIGHCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

nvdv2.03.3LOWAV:A/AC:L/Au:N/C:N/I:P/A:N

vendor_cisco7.4HIGH

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