What’s Vulnerable › Vulnerabilities

CVE-2023-20199: Cisco Duo Two-Factor Authentication for macOS Authentication Bypass Vulnerability

• Severity: medium (CVSS 6.6 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-06-28 · updated 2026-06-17
• Weakness: CWE-287

Description

A vulnerability in Cisco Duo Two-Factor Authentication for macOS could allow an authenticated, physical attacker to bypass secondary authentication and access an affected macOS device. This vulnerability is due to the incorrect handling of responses from Cisco Duo when the application is configured to fail open. An attacker with primary user credentials could exploit this vulnerability by attempting to authenticate to an affected device. A successful exploit could allow the attacker to access the affected device without valid permission.

Affected products

• Cisco Duo: from 2.0.0 before 2.0.2 — fixed in 2.0.2

How to fix

Upgrade to a fixed version: Cisco Duo 2.0.2. Check the vendor advisory for mitigations.

References

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-duo-mac-bypass-OyZpVPnx
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-duo-mac-bypass-OyZpVPnx

Get alerted when CVE-2023-20199 or the next vulnerability affects your stack