CVE-2026-20033

Cisco NX-OS Software Denial of Service Vulnerability

Published Feb 25, 2026 CVSS 3.1 · 7.4 High EPSS < 1% KEV · Not listed

Description

A vulnerability in Cisco Nexus 9000 Series Fabric Switches in ACI mode could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device.

This vulnerability is due to insufficient validation when processing specific Ethernet frames. An attacker could exploit this vulnerability by sending a crafted Ethernet frame to the management interface of an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition.
Note: Only the out-of-band (OOB) management interface is affected.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Cisco

Cisco NX-OS System Software in ACI Mode

unknown

Version	Status	Constraints
`15.2(1g)`	affected	—
`15.2(2e)`	affected	—
`15.2(2f)`	affected	—
`15.2(2g)`	affected	—
`15.2(2h)`	affected	—
`15.2(3f)`	affected	—
`15.2(3e)`	affected	—
`15.2(3g)`	affected	—
`15.2(4d)`	affected	—
`15.2(4e)`	affected	—
`15.2(5c)`	affected	—
`15.2(5d)`	affected	—
`16.0(1g)`	affected	—
`15.2(5e)`	affected	—
`15.2(4f)`	affected	—
`15.2(6e)`	affected	—
`15.2(6h)`	affected	—
`16.0(1j)`	affected	—
`15.2(6g)`	affected	—
`15.2(7f)`	affected	—
`15.2(7g)`	affected	—
`16.0(2h)`	affected	—
`15.2(8d)`	affected	—
`16.0(2j)`	affected	—
`15.2(8e)`	affected	—
`16.0(3d)`	affected	—
`16.0(3e)`	affected	—
`15.2(8f)`	affected	—
`15.2(8g)`	affected	—
`15.3(1d)`	affected	—
`15.2(8h)`	affected	—
`16.0(4c)`	affected	—
`15.3(2a)`	affected	—
`15.2(8i)`	affected	—
`16.0(5h)`	affected	—
`15.3(2b)`	affected	—
`16.0(3g)`	affected	—
`16.0(5j)`	affected	—
`15.3(2c)`	affected	—
`16.0(6c)`	affected	—
`15.3(2d)`	affected	—
`16.1(1f)`	affected	—
`16.0(7e)`	affected	—
`16.0(8e)`	affected	—
`15.3(2e)`	affected	—
`16.0(8f)`	affected	—
`16.1(2f)`	affected	—
`16.1(2g)`	affected	—
`15.3(2f)`	affected	—
`16.0(9c)`	affected	—
`16.1(3f)`	affected	—
`16.0(9d)`	affected	—
`16.0(6h)`	affected	—
`16.0(8h)`	affected	—
`16.1(3g)`	affected	—
`16.0(9e)`	affected	—
`16.1(4h)`	affected	—

No data.

Vendor Product Versions

Cisco

Cisco Nx-os System Software In Aci Mode

Version	Status	Scheme	Platform
`15.2(1g)`	affected	generic	—
`15.2(2e)`	affected	generic	—
`15.2(2f)`	affected	generic	—
`15.2(2g)`	affected	generic	—
`15.2(2h)`	affected	generic	—
`15.2(3f)`	affected	generic	—
`15.2(3e)`	affected	generic	—
`15.2(3g)`	affected	generic	—
`15.2(4d)`	affected	generic	—
`15.2(4e)`	affected	generic	—
`15.2(5c)`	affected	generic	—
`15.2(5d)`	affected	generic	—
`16.0(1g)`	affected	generic	—
`15.2(5e)`	affected	generic	—
`15.2(4f)`	affected	generic	—
`15.2(6e)`	affected	generic	—
`15.2(6h)`	affected	generic	—
`16.0(1j)`	affected	generic	—
`15.2(6g)`	affected	generic	—
`15.2(7f)`	affected	generic	—
`15.2(7g)`	affected	generic	—
`16.0(2h)`	affected	generic	—
`15.2(8d)`	affected	generic	—
`16.0(2j)`	affected	generic	—
`15.2(8e)`	affected	generic	—
`16.0(3d)`	affected	generic	—
`16.0(3e)`	affected	generic	—
`15.2(8f)`	affected	generic	—
`15.2(8g)`	affected	generic	—
`15.3(1d)`	affected	generic	—
`15.2(8h)`	affected	generic	—
`16.0(4c)`	affected	generic	—
`15.3(2a)`	affected	generic	—
`15.2(8i)`	affected	generic	—
`16.0(5h)`	affected	generic	—
`15.3(2b)`	affected	generic	—
`16.0(3g)`	affected	generic	—
`16.0(5j)`	affected	generic	—
`15.3(2c)`	affected	generic	—
`16.0(6c)`	affected	generic	—
`15.3(2d)`	affected	generic	—
`16.1(1f)`	affected	generic	—
`16.0(7e)`	affected	generic	—
`16.0(8e)`	affected	generic	—
`15.3(2e)`	affected	generic	—
`16.0(8f)`	affected	generic	—
`16.1(2f)`	affected	generic	—
`16.1(2g)`	affected	generic	—
`15.3(2f)`	affected	generic	—
`16.0(9c)`	affected	generic	—
`16.1(3f)`	affected	generic	—
`16.0(9d)`	affected	generic	—
`16.0(6h)`	affected	generic	—
`16.0(8h)`	affected	generic	—
`16.1(3g)`	affected	generic	—
`16.0(9e)`	affected	generic	—
`16.1(4h)`	affected	generic	—

Remediation

No solution or workaround provided in the CVE record

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Adjacent Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.173% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-cpdos-qLsv6pFD

History

Nov 10, 2026 9:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Feb 26, 2026 1:30 PM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Cisco Cisco cisco Nx-os System Software In Aci Mode
Vendors & Products		Cisco Cisco cisco Nx-os System Software In Aci Mode

Feb 25, 2026 5:15 PM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		A vulnerability in Cisco Nexus 9000 Series Fabric Switches in ACI mode could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation when processing specific Ethernet frames. An attacker could exploit this vulnerability by sending a crafted Ethernet frame to the management interface of an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition. Note: Only the out-of-band (OOB) management interface is affected.
Title		Cisco NX-OS Software Denial of Service Vulnerability
Weaknesses		CWE-805
References		https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-cpdos-qLsv6pFD
Metrics		cvssV3_1 `{'score': 7.4, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}`