How severe is CVE-2023-20168?

CVE-2023-20168 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-20168 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-20168?

CVE-2023-20168 primarily affects Cisco Nx-os. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-20168?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-20168 published?

CVE-2023-20168 was published on 2023-08-23 and last updated on 2026-06-17.

CVE-2023-20168

CVE-2023-20168 is a high-severity vulnerability in Cisco Nx-os with a CVSS 3.x base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Nx-os
Published: 2023-08-23
Last modified: 2026-06-17

Description

A vulnerability in TACACS+ and RADIUS remote authentication for Cisco NX-OS Software could allow an unauthenticated, local attacker to cause an affected device to unexpectedly reload. This vulnerability is due to incorrect input validation when processing an authentication attempt if the directed request option is enabled for TACACS+ or RADIUS. An attacker could exploit this vulnerability by entering a crafted string at the login prompt of an affected device. A successful exploit could allow the attacker to cause the affected device to unexpectedly reload, resulting in a denial of service (DoS) condition.

Frequently asked questions

What is CVE-2023-20168?: A vulnerability in TACACS+ and RADIUS remote authentication for Cisco NX-OS Software could allow an unauthenticated, local attacker to cause an affected device to unexpectedly reload. This vulnerability is due to incorrect input validation when processing an authentication attempt if the directed request option is enabled for TACACS+ or RADIUS. An attacker could exploit this vulnerability by entering a crafted string at the login prompt of an affected device. A successful exploit could allow the attacker to cause the affected device to unexpectedly reload, resulting in a denial of service (DoS) condition.
How severe is CVE-2023-20168?: CVE-2023-20168 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-20168 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-20168?: CVE-2023-20168 primarily affects Cisco Nx-os. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-20168?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-20168 published?: CVE-2023-20168 was published on 2023-08-23 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-remoteauth-dos-XB6pv74m

Affected products (3)

cpe:2.3:o:cisco:nx-os:9.3\(11\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:nx-os:10.2\(5\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:nx-os:-:*:*:*:*:*:*:*

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