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CVE-2023-20123

Status: ModifiedMedium (4.6)—

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.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (2)

Cisco — DUOCisco — DUO Authentication FOR Windows Logon AND RDP

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2023-20123",
  "cveTags": [],
  "metrics": {
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          "options": [
            {
              "exploitation": "none"
            },
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              "automatable": "no"
            },
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              "technicalImpact": "total"
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          "timestamp": "2024-10-28T16:19:09.134560Z"
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  "vulnStatus": "Modified",
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    }
  ],
  "lastModified": "2026-06-17T05:29:31.993",
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