CVE-2026-20033

HIGH

Cisco NX-OS System Software in ACI Mode - Unauthenticated Denial of Service via Crafted Ethernet Frame

Title source: llm
STIX 2.1

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.

References (1)

Core 1

Scores

CVSS v3 7.4
EPSS 0.0002
EPSS Percentile 6.0%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-805
Status published
Products (50)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(1g)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(2e)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(2f)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(2g)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(2h)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(3e)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(3f)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(3g)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(4d)
Cisco/Cisco NX-OS System Software in ACI Mode 15.2(4e)
... and 40 more
Published Feb 25, 2026
Tracked Since Feb 26, 2026