CVE-2021-1586

Cisco Nexus 9000 Series Fabric Switches ACI Mode Multi-Pod and Multi-Site TCP Denial of Service Vulnerability

HIGH
8.6
CVSS Score
Published: August 25, 2021 at 07:10 PM UTC
Updated: June 17, 2026 at 03:32 AM UTC
41 products affected across 1 vendorNx OSNexus 9508Nexus 93120Tx

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Severity
HIGH8.6
Exploit prediction
EPSS 2%
SSVC
No known exploit

Description

A vulnerability in the Multi-Pod or Multi-Site network configurations for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to unexpectedly restart the device, resulting in a denial of service (DoS) condition. This vulnerability exists because TCP traffic sent to a specific port on an affected device is not properly sanitized. An attacker could exploit this vulnerability by sending crafted TCP data to a specific port that is listening on a public-facing IP address for the Multi-Pod or Multi-Site configuration. A successful exploit could allow the attacker to cause the device to restart unexpectedly, resulting in a DoS condition.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

cisco-nexus-9000v (environment) · cisco-nexus-92160yc-x (environment) · cisco-nexus-92300yc (environment) · cisco-nexus-92304qc (environment) · cisco-nexus-92348gc-x (environment) · cisco-nexus-9236c (environment) · cisco-nexus-9272q (environment) · cisco-nexus-93108tc-ex (environment) · cisco-nexus-93108tc-ex-24 (environment) · cisco-nexus-93108tc-fx (environment) · cisco-nexus-93108tc-fx-24 (environment) · cisco-nexus-93108tc-fx3p (environment) · cisco-nexus-93120tx (environment) · cisco-nexus-93128tx (environment) · cisco-nexus-9316d-gx (environment) · cisco-nexus-93180lc-ex (environment) · cisco-nexus-93180yc-ex (environment) · cisco-nexus-93180yc-ex-24 (environment) · cisco-nexus-93180yc-fx (environment) · cisco-nexus-93180yc-fx-24 (environment) · cisco-nexus-93180yc-fx3 (environment) · cisco-nexus-93180yc-fx3s (environment) · cisco-nexus-93216tc-fx2 (environment) · cisco-nexus-93240yc-fx2 (environment) · cisco-nexus-9332c (environment) · cisco-nexus-9332pq (environment) · cisco-nexus-93360yc-fx2 (environment) · cisco-nexus-9336c-fx2 (environment) · cisco-nexus-9336c-fx2-e (environment) · cisco-nexus-9348gc-fxp (environment) · cisco-nexus-93600cd-gx (environment) · cisco-nexus-9364c (environment) · cisco-nexus-9364c-gx (environment) · cisco-nexus-9372px (environment) · cisco-nexus-9372px-e (environment) · cisco-nexus-9372tx (environment) · cisco-nexus-9372tx-e (environment) · cisco-nexus-9396px (environment) · cisco-nexus-9396tx (environment) · cisco-nexus-9508 (environment)
All versions
All versions
All versions
All versions
All versions
All versions
All versions
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.6HIGHcisco
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-345

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