High severity · published Feb 25, 2026
CVE-2026-20033
Cisco NX-OS Software Denial of Service Vulnerability
7.4
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CN
Cisco NX-OS System Software in ACI Mode · Cisco
15.2(1g); 15.2(2e); 15.2(2f); 15.2(2g); 15.2(2h); 15.2(3f); +34 more · source: vendor
Affected product
CN
Cisco NX-OS System Software in ACI Mode
Cisco
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