CVE-2020-3165

mediumpriority · track · 34OT risk · elevatedEPSS 0.016 · 75 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.56% (75th) EPSS
CVSS 4.3 · medium
Is it mine?
20 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-26

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.

01

remediations

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

A vendor fix is available.

02

cvss

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

8.2
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–8.2

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9
v3.18.2highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 4.2
v3.08.2highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:Nsecondary · ENISA EU
v3.08.2highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:Nsecondary · psirt@cisco.com USexploitability 3.9 · impact 4.2
v3.08.2highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:Nsecondary · Cisco PSIRT US
v3.18.2highAV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:Nsecondary · FSTEC (BDU) RU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

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

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-798USprimaryCWE-798US
05

affected products (20)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-20200226-nxos-bgpmd5Cisco NX-OS Software Border Gateway Protocol MD5 Authentication Bypass Vulnerability2020-02-26csaf · cisco_csafUS

    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. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nxos-bgpmd5 ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nxos-bgpmd5"]

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafnvdNVDCVE.orgMITRE
published 2020-02-26modified 2026-06-17
10

references (7)

External citations — patches, advisories, analysis.

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