CVE detail

CVE-2021-1231 — CVE-2021-1231

Published 2021-02-24 · Modified 2026-06-17 · Vendor cisco · Product nx-os · Source nvd

MEDIUM

severity

CVSS-derived band

4.7

CVSS v3

0–10 scale

0.0024

EPSS probability

exploitation probability, 30d

16.0%

EPSS percentile

percentile vs all CVEs

NOT LISTED

CISA KEV

known exploited catalog

Description

A vulnerability in the Link Layer Discovery Protocol (LLDP) for Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, adjacent attacker to disable switching on a small form-factor pluggable (SFP) interface. This vulnerability is due to incomplete validation of the source of a received LLDP packet. An attacker could exploit this vulnerability by sending a crafted LLDP packet on an SFP interface to an affected device. A successful exploit could allow the attacker to disable switching on the SFP interface, which could disrupt network traffic.

Remediation

Product	Vulnerable range	Fixed version	Advisory
Cisco Cisco NX-OS System Software in ACI Mode	—	not specified	advisory ↗

References

cvedb.io · NVD · CISA KEV · FIRST EPSS · vendor advisories (CVE Program List v5). Informational only, no warranty — verify every remediation against the vendor advisory before acting on it. This product uses data from the NVD API but is not endorsed or certified by the NVD, CISA, FIRST.org or any vendor named. CVE® is a registered trademark of The MITRE Corporation.