high
7.4
CWE
284
Advisory Published
Updated

CVE-2021-1228: Cisco Nexus 9000 Series Fabric Switches ACI Mode Fabric Infrastructure VLAN Unauthorized Access Vulnerability

First published: Wed Feb 24 2021(Updated: )

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.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco NX-OS=11.0\(1b\)
Cisco NX-OS=11.0\(1c\)
Cisco NX-OS=11.0\(1d\)
Cisco NX-OS=11.0\(1e\)
Cisco NX-OS=11.0\(2j\)
Cisco NX-OS=11.0\(2m\)
Cisco NX-OS=11.0\(3f\)
Cisco NX-OS=11.0\(3i\)
Cisco NX-OS=11.0\(3k\)
Cisco NX-OS=11.0\(3n\)
Cisco NX-OS=11.0\(3o\)
Cisco NX-OS=11.0\(4g\)
Cisco NX-OS=11.0\(4h\)
Cisco NX-OS=11.0\(4o\)
Cisco NX-OS=11.0\(4q\)
Cisco NX-OS=11.1\(1j\)
Cisco NX-OS=11.1\(1o\)
Cisco NX-OS=11.1\(1r\)
Cisco NX-OS=11.1\(1s\)
Cisco NX-OS=11.1\(2h\)
Cisco NX-OS=11.1\(2i\)
Cisco NX-OS=11.1\(3f\)
Cisco NX-OS=11.1\(4e\)
Cisco NX-OS=11.1\(4f\)
Cisco NX-OS=11.1\(4g\)
Cisco NX-OS=11.1\(4i\)
Cisco NX-OS=11.1\(4l\)
Cisco NX-OS=11.1\(4m\)
Cisco NX-OS=11.2\(1i\)
Cisco NX-OS=11.2\(1k\)
Cisco NX-OS=11.2\(1m\)
Cisco NX-OS=11.2\(2g\)
Cisco NX-OS=11.2\(2h\)
Cisco NX-OS=11.2\(2i\)
Cisco NX-OS=11.2\(2j\)
Cisco NX-OS=11.2\(3c\)
Cisco NX-OS=11.2\(3e\)
Cisco NX-OS=11.2\(3h\)
Cisco NX-OS=11.2\(3m\)
Cisco NX-OS=11.3\(1g\)
Cisco NX-OS=11.3\(1h\)
Cisco NX-OS=11.3\(1i\)
Cisco NX-OS=11.3\(1j\)
Cisco NX-OS=11.3\(2f\)
Cisco NX-OS=11.3\(2h\)
Cisco NX-OS=11.3\(2i\)
Cisco NX-OS=11.3\(2j\)
Cisco NX-OS=11.3\(2k\)
Cisco NX-OS=12.0\(1m\)
Cisco NX-OS=12.0\(1n\)
Cisco NX-OS=12.0\(1o\)
Cisco NX-OS=12.0\(1p\)
Cisco NX-OS=12.0\(1q\)
Cisco NX-OS=12.0\(1r\)
Cisco NX-OS=12.0\(2f\)
Cisco NX-OS=12.0\(2g\)
Cisco NX-OS=12.0\(2h\)
Cisco NX-OS=12.0\(2l\)
Cisco NX-OS=12.0\(2m\)
Cisco NX-OS=12.0\(2n\)
Cisco NX-OS=12.0\(2o\)
Cisco NX-OS=12.1\(1h\)
Cisco NX-OS=12.1\(1i\)
Cisco NX-OS=12.1\(2e\)
Cisco NX-OS=12.1\(2g\)
Cisco NX-OS=12.1\(2k\)
Cisco NX-OS=12.1\(3g\)
Cisco NX-OS=12.1\(3h\)
Cisco NX-OS=12.1\(3j\)
Cisco NX-OS=12.1\(4a\)
Cisco NX-OS=12.2\(1k\)
Cisco NX-OS=12.2\(1n\)
Cisco NX-OS=12.2\(1o\)
Cisco NX-OS=12.2\(2e\)
Cisco NX-OS=12.2\(2f\)
Cisco NX-OS=12.2\(2i\)
Cisco NX-OS=12.2\(2j\)
Cisco NX-OS=12.2\(2k\)
Cisco NX-OS=12.2\(2q\)
Cisco NX-OS=12.2\(3j\)
Cisco NX-OS=12.2\(3p\)
Cisco NX-OS=12.2\(3r\)
Cisco NX-OS=12.2\(3s\)
Cisco NX-OS=12.2\(3t\)
Cisco NX-OS=12.2\(4f\)
Cisco NX-OS=12.2\(4p\)
Cisco NX-OS=12.2\(4q\)
Cisco NX-OS=12.2\(4r\)
Cisco NX-OS=12.3\(1e\)
Cisco NX-OS=12.3\(1f\)
Cisco NX-OS=12.3\(1i\)
Cisco NX-OS=12.3\(1l\)
Cisco NX-OS=12.3\(1o\)
Cisco NX-OS=12.3\(1p\)
Cisco NX-OS=13.0\(1k\)
Cisco NX-OS=13.0\(2h\)
Cisco NX-OS=13.0\(2k\)
Cisco NX-OS=13.0\(2n\)
Cisco NX-OS=13.1\(1i\)
Cisco NX-OS=13.1\(2m\)
Cisco NX-OS=13.1\(2o\)
Cisco NX-OS=13.1\(2p\)
Cisco NX-OS=13.1\(2q\)
Cisco NX-OS=13.1\(2s\)
Cisco NX-OS=13.1\(2t\)
Cisco NX-OS=13.1\(2u\)
Cisco NX-OS=13.1\(2v\)
Cisco NX-OS=13.2\(1l\)
Cisco NX-OS=13.2\(1m\)
Cisco NX-OS=13.2\(2l\)
Cisco NX-OS=13.2\(2o\)
Cisco NX-OS=13.2\(3i\)
Cisco NX-OS=13.2\(3j\)
Cisco NX-OS=13.2\(3n\)
Cisco NX-OS=13.2\(3o\)
Cisco NX-OS=13.2\(3r\)
Cisco NX-OS=13.2\(3s\)
Cisco NX-OS=13.2\(4d\)
Cisco NX-OS=13.2\(4e\)
Cisco NX-OS=13.2\(5d\)
Cisco NX-OS=13.2\(5e\)
Cisco NX-OS=13.2\(5f\)
Cisco NX-OS=13.2\(6i\)
Cisco NX-OS=13.2\(7f\)
Cisco NX-OS=13.2\(7k\)
Cisco NX-OS=13.2\(8d\)
Cisco NX-OS=13.2\(9b\)
Cisco NX-OS=13.2\(9f\)
Cisco NX-OS=13.2\(9h\)
Cisco NX-OS=13.2\(41d\)
Cisco NX-OS=14.0\(1h\)
Cisco NX-OS=14.0\(2c\)
Cisco NX-OS=14.0\(3c\)
Cisco NX-OS=14.0\(3d\)
Cisco NX-OS=14.1\(1i\)
Cisco NX-OS=14.1\(1j\)
Cisco NX-OS=14.1\(1k\)
Cisco NX-OS=14.1\(1l\)
Cisco NX-OS=14.1\(2g\)
Cisco NX-OS=14.1\(2m\)
Cisco NX-OS=14.1\(2o\)
Cisco NX-OS=14.1\(2s\)
Cisco NX-OS=14.1\(2u\)
Cisco NX-OS=14.1\(2w\)
Cisco NX-OS=14.1\(2x\)
Cisco NX-OS=14.2\(1i\)
Cisco NX-OS=14.2\(1j\)
Cisco NX-OS=14.2\(1l\)
Cisco NX-OS=14.2\(2e\)
Cisco NX-OS=14.2\(2f\)
Cisco NX-OS=14.2\(3j\)
Cisco NX-OS=14.2\(3l\)
Cisco NX-OS=14.2\(3n\)
Cisco NX-OS=14.2\(3q\)
Cisco NX-OS=14.2\(4i\)
Cisco NX-OS=14.2\(4k\)
Cisco NX-OS=14.2\(4o\)
Cisco NX-OS=14.2\(4p\)
Cisco NX-OS=14.2\(5k\)
Cisco NX-OS=15.0\(1k\)
Cisco NX-OS=15.0\(1l\)
Cisco NX-OS=15.0\(2h\)
Cisco NX-OS Nexus 9000 Series
Cisco Nexus 92160YC Switch
Cisco Nexus 92300YC Firmware
Cisco Nexus 92304QC Switch
Cisco Nexus 92348GC-X Switch
Cisco Nexus 9236C Switch
Cisco Nexus 9272Q Switch
Cisco Nexus
Cisco Nexus 93108TC-EX-24 Firmware
Cisco Nexus 93108TC-FX Switch
Cisco Nexus 93108TC-FX Switch
Cisco Nexus 93120TX Firmware
Cisco Nexus 93128 Firmware
Cisco Nexus 9316D-GX Firmware
Cisco Nexus 93180LC-EX Switch
Cisco Nexus 93180YC-EX-24
Cisco Nexus 93180YC-EX-24 Firmware
Cisco Nexus 93180YC-FX Firmware
Cisco Nexus 93180YC-FX-24 Firmware
Cisco Nexus 93180YC-FX3 Firmware
Cisco Nexus 93180YC-FX3S Firmware
Cisco Nexus 93216TC-FX2 Firmware
Cisco Nexus 93240YC-FX2 Firmware
Cisco Nexus 9332C Firmware
Cisco Nexus 9332PQ Firmware
Cisco Nexus 93360YC-FX2
Cisco Nexus 9336C-FX2 Firmware
Cisco Nexus 9336C-FX2-E Firmware
Cisco Nexus N9336PQ-X
Cisco Nexus 9348GC-FXP Firmware
Cisco Nexus 93600CD-GX Firmware
Cisco Nexus 9364c-h1
Cisco Nexus 9364C-GX Firmware
Cisco Nexus 9372PX-E
Cisco Nexus 9372PX-E Firmware
Cisco Nexus 9372TX
Cisco Nexus 9372TX-E Switch
Cisco Nexus 9396PX Firmware
Cisco Nexus 9396TX Firmware
Cisco Nexus 9508

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-1228?

    CVE-2021-1228 is considered high severity as it allows an unauthenticated, adjacent attacker to bypass security validations.

  • How do I fix CVE-2021-1228?

    To fix CVE-2021-1228, upgrade to the latest version of Cisco NX-OS that addresses this vulnerability.

  • What Cisco products are affected by CVE-2021-1228?

    CVE-2021-1228 affects Cisco Nexus 9000 Series Fabric Switches running specific versions of NX-OS, including 11.0(1b) through 14.x versions.

  • Can CVE-2021-1228 be exploited remotely?

    No, CVE-2021-1228 can only be exploited by an adjacent attacker on the same local network.

  • What types of attacks can be performed using CVE-2021-1228?

    An attacker exploiting CVE-2021-1228 can connect unauthorized servers to the network, potentially gaining access to sensitive information.

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