Cisco Nexus 9000 Series Fabric Switches ACI Mode Fabric Infrastructure VLAN Unauthorized Access (cisco-sa-n9kaci-unauth-access-5PWzDx2w)

medium Nessus Plugin ID 149368
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Synopsis

The remote device is missing a vendor-supplied security patch

Description

According to its self-reported version, the fabric infrastructure VLAN connection establishment of Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) is affected by unauthorized access vulnerability due to insufficient security requirements during the Link Layer Discovery Protocol (LLDP) setup phase of the infrastructure VLAN. An unauthenticated, adjacent attacker could exploit this by sending a crafted LLDP packet on the adjacent subnet to an affected device. 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. no workarounds that address this vulnerability.

Please see the included Cisco BID and Cisco Security Advisory for more information.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to the relevant fixed version referenced in Cisco bug IDs CSCvu84576

See Also

http://www.nessus.org/u?0064df70

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvu84576

Plugin Details

Severity: Medium

ID: 149368

File Name: cisco-sa-n9kaci-unauth-access-5PWzDx2w.nasl

Version: 1.4

Type: combined

Family: CISCO

Published: 5/11/2021

Updated: 5/12/2021

Dependencies: cisco_nxos_version.nasl

Risk Information

CVSS Score Source: CVE-2021-1228

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Low

Base Score: 3.3

Temporal Score: 2.4

Vector: AV:A/AC:L/Au:N/C:N/I:P/A:N

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.7

Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:cisco:nx-os

Required KB Items: Host/Cisco/NX-OS/Version, Host/aci/system/chassis/summary, Host/Cisco/NX-OS/Model, Host/Cisco/NX-OS/Device

Exploit Ease: No known exploits are available

Patch Publication Date: 2/24/2021

Vulnerability Publication Date: 2/24/2021

Reference Information

CVE: CVE-2021-1228