{"cve":"CVE-2020-3165","nvd":{"published":"2020-02-26T17:15:12.673","modified":"2026-06-17T03:17:31.947","status":"Modified","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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N","score":8.2},"cwes":["CWE-798"],"references":["https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nxos-bgpmd5","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nxos-bgpmd5"],"products":["cisco:nx-os"],"source":"nvd","synced_at":"2026-10-19T21:02:53.949909883+00:00"},"epss":{"cve":"CVE-2020-3165","score":0.01563,"percentile":0.75269,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}