CVE-2021-1228

lowpriority · track · 26EPSS 0.004 · 33 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.39% (33rd) EPSS
CVSS 3.3 · low
Is it mine?
235 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the fabric infrastructure VLAN connection establishment of Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, adjacent attacker to bypass security validations and connect an unauthorized server to the infrastructure VLAN. This 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 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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • FixedCisco NX-OS System Software in ACI Mode 13.2(1l) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(1m) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(2l) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(2o) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(3i) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(3j) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(3n) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(3o) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(3r) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(3s) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(41d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(4d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(4e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(5d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(5e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(5f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(6i) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(7f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(7k) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(8d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(9b) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(9f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 13.2(9h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.0(1h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.0(2c) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.0(3c) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.0(3d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(1i) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(1j) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(1k) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(1l) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2g) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2m) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2o) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2s) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2u) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2w) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.1(2x) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(1i) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(1j) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(1l) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(2e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(2f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(2g) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(3j) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(3l) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(3n) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(3q) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(4i) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(4k) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(4o) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(4p) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 14.2(5k) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 15.0(1k) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 15.0(1l) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 15.0(2e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco NX-OS System Software in ACI Mode 15.0(2h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
02

cvss

Technical severity, 0–10. One row per scoring source.

7.4
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.3–7.4

v2.03.3lowAV:A/AC:L/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 6.5 · impact 2.9
v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 3.6
v3.17.4highAV:A/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:Nsecondary · FSTEC (BDU) RU
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:Nsecondary · ENISA EU
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:Nsecondary · psirt@cisco.com USexploitability 2.8 · impact 4
v3.16mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:Nsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-284USCWE-284US
05

affected products (235)

Products and version ranges known to be affected.

showing 20 of 235
06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-n9kaci-unauth-access-5PWzDx2wCisco Nexus 9000 Series Fabric Switches ACI Mode Fabric Infrastructure VLAN Unauthorized Access Vulnerability2021-02-24csaf · cisco_csafUS

    A vulnerability in the fabric infrastructure VLAN connection establishment of Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, adjacent attacker to bypass security validations and connect an unauthorized server to the infrastructure VLAN. This 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 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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-unauth-access-5PWzDx2w ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-unauth-access-5PWzDx2w"] This advisory is part of the February 2021 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: February 2021 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74414"].

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafNVDCVE.orgMITRE
published 2021-02-24modified 2026-06-17
09

references (6)

External citations — patches, advisories, analysis.

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