CVE-2021-1588

Cisco NX-OS Software MPLS OAM Denial of Service Vulnerability

HIGH

8.6

CVSS Score

Published: August 25, 2021 at 07:11 PM UTC

Updated: June 17, 2026 at 03:32 AM UTC

67 products affected across 1 vendorNx OSNexus 9508Nexus 93120Tx

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Severity

HIGH8.6

Exploit prediction

EPSS 1%

SSVC

No known exploit

Description

A vulnerability in the MPLS Operation, Administration, and Maintenance (OAM) feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper input validation when an affected device is processing an MPLS echo-request or echo-reply packet. An attacker could exploit this vulnerability by sending malicious MPLS echo-request or echo-reply packets to an interface that is enabled for MPLS forwarding on the affected device. A successful exploit could allow the attacker to cause the MPLS OAM process to crash and restart multiple times, causing the affected device to reload and resulting in a DoS condition.

Affected

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

Nx OS · Cisconpm

95%

7.0(3)i7(9)8.4(1)9.3(7)

cisco-nexus-3000 (environment) · cisco-nexus-3048 (environment) · cisco-nexus-31108pc-v (environment) · cisco-nexus-31108tc-v (environment) · cisco-nexus-31128pq (environment) · cisco-nexus-3132c-z (environment) · cisco-nexus-3132q-v (environment) · cisco-nexus-3132q-x-3132q-xl (environment) · cisco-nexus-3164q (environment) · cisco-nexus-3172pq-pq-xl (environment) · cisco-nexus-3172tq-xl (environment) · cisco-nexus-3232c (environment) · cisco-nexus-3264c-e (environment) · cisco-nexus-3264q (environment) · cisco-nexus-3408-s (environment) · cisco-nexus-34180yc (environment) · cisco-nexus-3432d-s (environment) · cisco-nexus-3464c (environment) · cisco-nexus-3524-x-xl (environment) · cisco-nexus-3548-x-xl (environment) · cisco-nexus-36180yc-r (environment) · cisco-nexus-3636c-r (environment) · cisco-nexus-7000-10-slot (environment) · cisco-nexus-7000-18-slot (environment) · cisco-nexus-7000-4-slot (environment) · cisco-nexus-7000-9-slot (environment) · 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)

Nexus 3000 · Ciscodevice

80%

All versions

Nexus 3048 · Ciscodevice

80%

All versions

Nexus 31108Pc-V · Ciscodevice

80%

All versions

Nexus 31108Tc-V · Ciscodevice

80%

All versions