Cyber Resilience

CVE-2024-20301

Auth Bypass in Cisco Duo Authentication For Windows Logon And Rdp 4.2.0 – 4.3.0

Auth Bypass
Published
06 March 2024
Modified
17 June 2026
Patch / advisory
View advisory
CVSS Score v3.1 6.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:P/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0027 18th percentile
Risk Priority 45 floored blend · peak EPSS

Summary

CVE-2024-20301 is a medium-severity Improper Authentication (CWE-287) vulnerability in Cisco Duo Authentication For Windows Logon And Rdp. Its CVSS base score is 6.2 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique External Remote Services (T1133); ranked at the 18th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-12 (Session Termination) and IA-2 (Identification and Authentication (Organizational Users)) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A07:2025 Authentication Failures

EU & UK References

Vulnerability Data

A vulnerability in Cisco Duo Authentication for Windows Logon and RDP could allow an authenticated, physical attacker to bypass secondary authentication and access an affected Windows device. This vulnerability is due to a failure to invalidate locally created trusted sessions…

more

after a reboot of the affected device. 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 permissions.

CWE(s)
CWE-287CWE-613

Related Threats

MITRE ATT&CK Enterprise Techniques

T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
attack.mitre.org →
T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1550 Use Alternate Authentication Material Lateral Movement
Adversaries may use alternate authentication material, such as password hashes, Kerberos tickets, and application access tokens, in order to move laterally within an environment and bypass normal system access controls.
attack.mitre.org →
T1550.004 Web Session Cookie Lateral Movement
Adversaries can use stolen session cookies to authenticate to web applications and services.
attack.mitre.org →
T1563 Remote Service Session Hijacking Lateral Movement
Adversaries may take control of preexisting sessions with remote services to move laterally in an environment.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20292Same product: Cisco Duo Authentication For Windows Logon And Rdp
CVE-2023-20123Same product: Cisco Duo Authentication For Windows Logon And Rdp
CVE-2023-20238Same vendor: Cisco
CVE-2019-1937Same vendor: Cisco
CVE-2023-20199Same vendor: Cisco
CVE-2023-20012Same vendor: Cisco
CVE-2026-20127Same vendor: Cisco
CVE-2023-20214Same vendor: Cisco
CVE-2026-20182Same vendor: Cisco
CVE-2026-20129Same vendor: Cisco

Affected Assets

cisco
duo authentication for windows logon and rdp
4.2.0 — 4.3.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.4.4
  • V6.5.4
  • V6.5.5
  • V6.5.7

Mitigating Controls (NIST 800-53 r5) AI

AC-12 Session Termination good match

AC-12 directly requires automatic session termination after a defined period, structurally preventing reuse of expired session identifiers.

IA-2 Identification and Authentication (Organizational Users) good match

Mandates unique identification and authentication of organizational users before access, directly stopping improper authentication.

IA-3 Device Identification and Authentication good match

Requires unique identification and authentication of devices before establishing connections, preventing unauthenticated device claims.

IA-8 Identification and Authentication (Non-organizational Users) good match

Mandates unique identification and authentication of non-organizational users, directly addressing the weakness for external actors.

IA-5 Authenticator Management good match

Manages authenticators with verification and secure distribution, reducing opportunities for improper authentication.

AC-3 Access Enforcement partial match

Enforces access only after approved authorizations, which presupposes correct authentication has occurred.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-01 mostly match
prevents

Credential lifecycle management directly includes enforcing session expiration to prevent reuse.

PR.AA-03 mostly match
prevents

PR.AA-03 directly enforces authentication mechanisms that eliminate most improper-authentication defects, yet CWE-287 spans additional vectors (missing checks, flawed protocols, session handling) that one control does not fully close.

PR.AA-04 mostly match
prevents

PR.AA-04 directly enables verification of identity assertions (mostly preventing CWE-287 in that scope) yet leaves many other authentication failure modes unaddressed (only partial prevention overall).

PR.AA-05 mostly match
prevents

Authorization policy enforcement and review covers terminating stale sessions to limit access scope.

PR.AA-02 partial match
prevents

PR.AA-02 ensures valid enrollment and unique credential binding, which reduces some improper-auth risks at issuance time but leaves runtime claim verification untouched, so each direction only partially addresses the other.

PR.PS-01 partial match
prevents

PR.PS-01 can enforce auth-related settings via hardened baselines and default reviews, blocking some config-based instances of CWE-287, yet leaves code-level auth flaws untouched so neither direction reaches mostly.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.5 Secure authentication full match
prevents

Requiring authentication methods whose strength matches the sensitivity of the data and mandating multi-factor authentication directly blocks attempts to access resources without proving identity.

A.5.17 Authentication information mostly match
prevents

Verifying user identity before issuing replacement credentials and forcing changes after compromise reduces the likelihood that authentication bypass can be achieved through stolen or weak credentials.

A.5.16 Identity management partial match
prevents

Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.

A.8.21 Security of network services partial match
mitigates

Requiring authentication mechanisms and technical parameters for secure connections ensures that network services verify user identity before granting access, preventing exploitation of missing or weak authentication.

A.8.25 Secure development life cycle partial match
prevents

Security requirements specified early and verified through testing drive the consistent implementation of authentication mechanisms, decreasing the likelihood that authentication steps are omitted or incorrectly applied.

A.8.26 Application security requirements partial match
prevents

Defining the required level of trust in entity identity and the authentication mechanisms to achieve it ensures that authentication is explicitly addressed rather than omitted.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-287
RHEL 7 (3 rules)
  • V-204425 The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using an empty password. prevents CWE-287
  • V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-287
  • V-204424 The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. prevents CWE-287
RHEL 8 (1 rule)
  • V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-287
Ubuntu 22.04 (1 rule)
  • V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
Ubuntu 24.04 (2 rules)
  • V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
  • V-270714 Ubuntu 24.04 LTS must not allow accounts configured in Pluggable Authentication Modules (PAM) with blank or null passwords. prevents CWE-287

References