CVE-2020-3165 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N

Reference

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nxos-bgpmd5

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

LOW

Availability Impact

HIGH

Base Score

NONE

Base Severity

8.2