#VU123287 Use of uninitialized variable in Cisco NX-OS - CVE-2026-20051
Published: February 26, 2026
Vulnerability identifier: #VU123287
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-20051
CWE-ID: CWE-457
Exploitation vector: Adjecent network
Exploit availability:
No public exploit available
Vulnerable software:
Cisco NX-OS
Cisco NX-OS
Software vendor:
Cisco Systems, Inc
Cisco Systems, Inc
Description
The vulnerability allows a remote attacker to perform a denial of service attack.
The vulnerability exists due to improper input validation of the Ethernet VPN (EVPN) Layer 2 ingress packets. A remote attacker on the local network send specially crafted packets to the system, cause a Layer 2 Virtual eXtensible LAN (VxLAN) traffic loop and perform a denial of service attack.
Remediation
Install updates from vendor's website.