BugZero | Cisco BugID CSCwe72368 - Cisco NX-OS TACACS+ or RADIUS Remote Authenticatio...

Cisco - Defect ID: CSCwe72368

Cisco NX-OS TACACS+ or RADIUS Remote Authentication Directed Request DoS Vulnerability

Cisco - Defect ID: CSCwe72368

Cisco NX-OS TACACS+ or RADIUS Remote Authentication Directed Request DoS Vulnerability

Last updated on February 21st, 2026

BugZero Risk Score
6.1 Medium

Overall: 6.1

Severity: 6.4

Lifecycle: 9.1

Popularity: 5.1

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Bug Details

Description

Symptom

A vulnerability in TACACS+ and RADIUS remote authentication for Cisco NX-OS Software could allow an unauthenticated, local attacker to cause an affected device to unexpectedly reload. This vulnerability is due to incorrect input validation when processing an authentication attempt if the directed request option is enabled for TACACS+ or RADIUS. An attacker could exploit this vulnerability by entering a crafted string at the login prompt of an affected device. A successful exploit could allow the attacker to cause the affected device to unexpectedly reload, resulting in a denial of service (DoS) condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-remoteauth-dos-XB6pv74m The Cisco Product Security Incident Response Team (PSIRT) validates only the affected and fixed release information that is documented in this advisory.

Conditions

Please refer to the Security Advisory.

Workaround

Please refer to the Security Advisory.

Further Problem Description

Please refer to the Security Advisory.

PSIRT Evaluation

The Cisco PSIRT has assigned this bug the following CVSS version 3 score. The Base CVSS score as of the time of evaluation is 7.1: https://sec.cloudapps.cisco.com/security/center/cvssCalculator.x?vector=CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H CVE ID CVE-2023-20168 has been assigned to document this issue. Additional information on Cisco's security vulnerability policy can be found at the following URL: https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html

Change history

2025-12-05 Added: 6.2(10), 6.2(12), 6.2(14), 6.2(16), 6.2(18), 6.2(2), 6.2(20), 6.2(20a), 6.2(22), 6.2(24), 6.2(24a), 6.2(2a), 6.2(6), 6.2(6a), 6.2(6b), 6.2(8), 6.2(8a), 6.2(8b), 7.2(0)D1(1), 7.2(1)D1(1), 7.2(2)D1(1), 7.2(2)D1(2), 7.3(0)D1(1), 7.3(0)DX(1), 7.3(1)D1(1), 7.3(2)D1(1), 7.3(2)D1(2), 7.3(2)D1(3), 7.3(2)D1(3a), 7.3(3)D1(1), 7.3(4)D1(1), 7.3(5)D1(1), 7.3(6)D1(1), 7.3(7)D1(1), 7.3(8)D1(1), 7.3(9)D1(1), 8.0(1), 8.1(1), 8.1(2), 8.1(2a), 8.2(1), 8.2(2), 8.2(3), 8.2(4), 8.2(5), 8.2(6), 8.2(7), 8.2(7a), 8.2(8), 8.2(9), 8.3(1), 8.3(2), 8.4(1), 8.4(2), 8.4(3), 8.4(4), 8.4(4a), 8.4(5), 8.4(6), 8.4(6a), 8.4(7)

Relevant Products

Click on a version to see all relevant bugs

Affected versions:6.2(10), 6.2(12), 6.2(14), 6.2(16), 6.2(18), 6.2(2), 6.2(20), 6.2(20a), 6.2(22), 6.2(24), 6.2(24a), 6.2(2a), 6.2(6), 6.2(6a), 6.2(6b), 6.2(8), 6.2(8a), 6.2(8b), 7.2(0)D1(1), 7.2(1)D1(1), 7.2(2)D1(1), 7.2(2)D1(2), 7.3(0)D1(1), 7.3(0)DX(1), 7.3(1)D1(1), 7.3(2)D1(1), 7.3(2)D1(2), 7.3(2)D1(3), 7.3(2)D1(3a), 7.3(3)D1(1), 7.3(4)D1(1), 7.3(5)D1(1), 7.3(6)D1(1), 7.3(7)D1(1), 7.3(8)D1(1), 7.3(9)D1(1), 8.0(1), 8.1(1), 8.1(2), 8.1(2a), 8.2(1), 8.2(2), 8.2(3), 8.2(4), 8.2(5), 8.2(6), 8.2(7), 8.2(7a), 8.2(8), 8.2(9), 8.3(1), 8.3(2), 8.4(1), 8.4(2), 8.4(3), 8.4(4), 8.4(4a), 8.4(5), 8.4(6), 8.4(6a), 8.4(7)

Fixed versions: 8.2(10), 8.2(11), 8.4(10), 8.4(11), 8.4(12), 8.4(13), 8.4(8), 8.4(9)

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 8.2(10), 8.2(11), 8.4(10), 8.4(11), 8.4(12), 8.4(13), 8.4(8), 8.4(9)

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Cisco - Defect ID: CSCwe72368

Cisco NX-OS TACACS+ or RADIUS Remote Authentication Directed Request DoS Vulnerability

Cisco - Defect ID: CSCwe72368

Cisco NX-OS TACACS+ or RADIUS Remote Authentication Directed Request DoS Vulnerability

Last updated on February 21st, 2026

BugZero Risk Score6.1 Medium

Bug Details

Symptom

Conditions

Workaround

Further Problem Description

PSIRT Evaluation

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BugZero Risk Score
6.1 Medium