high
8.2
CWE
798
Advisory Published
Updated

CVE-2020-3165: Cisco NX-OS Software Border Gateway Protocol MD5 Authentication Bypass Vulnerability

First published: Wed Feb 26 2020(Updated: )

A vulnerability in the implementation of Border Gateway Protocol (BGP) Message Digest 5 (MD5) authentication in Cisco NX-OS Software could allow an unauthenticated, remote attacker to bypass MD5 authentication and establish a BGP connection with the device. The vulnerability occurs because the BGP MD5 authentication is bypassed if the peer does not have MD5 authentication configured, the NX-OS device does have BGP MD5 authentication configured, and the NX-OS BGP virtual routing and forwarding (VRF) name is configured to be greater than 19 characters. An attacker could exploit this vulnerability by attempting to establish a BGP session with the NX-OS peer. A successful exploit could allow the attacker to establish a BGP session with the NX-OS device without MD5 authentication. The Cisco implementation of the BGP protocol accepts incoming BGP traffic only from explicitly configured peers. To exploit this vulnerability, an attacker must send the malicious packets over a TCP connection that appears to come from a trusted BGP peer. To do so, the attacker must obtain information about the BGP peers in the affected system’s trusted network.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco NX-OS=9.2\(1\)
Cisco NX-OS=9.2\(2\)
Cisco NX-OS=9.2\(3\)
Cisco NX-OS=9.3\(1\)
Cisco Nexus 3016Q Firmware
Cisco Nexus 3048 Firmware
Cisco Nexus 3064 Firmware
Cisco Nexus 3064
Cisco Nexus 31108PC-V Firmware
Cisco Nexus 31108TC-V Firmware
Cisco Nexus 31128PQ
Cisco Nexus 3132C-Z Firmware
Cisco Nexus 3132Q-XL
Cisco Nexus 3132Q-V Firmware
Cisco Nexus 3132Q-XL Firmware
Cisco Nexus 3164Q Firmware
Cisco Nexus 3172 Firmware
Cisco Nexus 3172PQ-XL Firmware
Cisco Nexus 3172TQ Firmware
Cisco Nexus 3172TQ-XL
Cisco Nexus 3172TQ-XL Firmware
Cisco Nexus 3232C
Cisco Nexus 3264C-E Firmware
Cisco Nexus 3264Q Firmware
Cisco Nexus 3408-S Firmware
Cisco Nexus 34180YC Firmware
Cisco Nexus 3432D-S Firmware
Cisco Nexus 3464C Firmware
Cisco Nexus 3524-xl
Cisco Nexus 3524-xl
Cisco Nexus 3524-X/XL
Cisco Nexus 3548-X/XL Firmware
Cisco Nexus 3548-X/XL
Cisco Nexus 3548-X/XL
Cisco Nexus 36180YC-R Firmware
Cisco Nexus 3636C-R Firmware
Cisco NX-OS Nexus 9000 Series
Cisco Nexus 92160YC Switch
Cisco Nexus 92300YC Firmware
Cisco Nexus 92304QC Firmware
Cisco Nexus 92348GC-X Switch
Cisco Nexus 9236C
Cisco Nexus 9272Q Switch
Cisco Nexus
Cisco Nexus 93108TC-FX Switch
Cisco Nexus 93120TX Firmware
Cisco Nexus 93128TX
Cisco Nexus 9000 Series Switch
Cisco Nexus 93180YC-EX-24
Cisco Nexus 93180YC-FX 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 N9336PQ-X
Cisco Nexus 9348GC-FXP Firmware
Cisco Nexus 9364c-h1
Cisco Nexus 9372PX-E
Cisco Nexus 9372PX-E Firmware
Cisco Nexus 9372TX Firmware
Cisco Nexus 9372TX-E Switch
Cisco Nexus 9396PX Firmware
Cisco Nexus 9396TX Firmware
Cisco Nexus 9504 Firmware
Cisco Nexus 9508
Cisco Nexus 9516 firmware

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Reference Links

Frequently Asked Questions

  • What is CVE-2020-3165?

    CVE-2020-3165 is a vulnerability in the implementation of Border Gateway Protocol (BGP) Message Digest 5 (MD5) authentication in Cisco NX-OS Software.

  • How does CVE-2020-3165 affect Cisco NX-OS Software?

    CVE-2020-3165 allows an unauthenticated, remote attacker to bypass MD5 authentication and establish a BGP connection with the device.

  • What is the severity of CVE-2020-3165?

    The severity of CVE-2020-3165 is high with a CVSS score of 8.2.

  • How can I fix CVE-2020-3165?

    To fix CVE-2020-3165, it is recommended to upgrade to a fixed software release as mentioned in the Cisco Security Advisory.

  • Where can I find more information about CVE-2020-3165?

    You can find more information about CVE-2020-3165 in the Cisco Security Advisory linked in the references.

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