Duo
CVE-2023-20123
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A07:2025 - Authentication Failures
ASVS 5.0
V6 - Authentication Replay attack prevention
|
| Impact | CVSS score of 4.6 (MEDIUM). Attack characteristics: physical attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAI
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. Rated medium severity (CVSS 4.6), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-294. 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. Affected products include: Cisco Duo, Cisco Duo Authentication For Windows Logon And Rdp.
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Severity by source
AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
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.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)NVD
The Duo Authentication Proxy installer prior to 5.2.1 did not properly validate file installation paths. Rated high seve
A vulnerability in the smart card login authentication of Cisco Duo for macOS could allow an unauthenticated attacker wi
A vulnerability in Cisco Duo Two-Factor Authentication for macOS could allow an authenticated, physical attacker to bypa
A vulnerability in the logging component of Cisco Duo Authentication Proxy could allow an authenticated, remote attacker
The DuoConnect client enables users to establish SSH connections to hosts protected by a DNG instance. Rated medium seve
A vulnerability in the self-service portal of Cisco Duo could allow an unauthenticated, remote attacker to inject arbitr
GitHub PoC
Exploit-DB