high
8.6
CWE
126 20 125
Advisory Published
Updated

CVE-2021-1588: Cisco NX-OS Software MPLS OAM Denial of Service Vulnerability

First published: Wed Aug 25 2021(Updated: )

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.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco NX-OS=7.0\(3\)i7\(9\)
Cisco NX-OS=8.4\(1\)
Cisco NX-OS=9.3\(7\)
Cisco Nexus 3000
Cisco Nexus 3048 Firmware
Cisco Nexus 31108PC-V Firmware
Cisco Nexus 31108TC-V Firmware
Cisco Nexus 31128PQ
Cisco Nexus 3132C-Z Firmware
Cisco Nexus 3132Q-V Firmware
Cisco Nexus 3132Q-X/3132Q-XL
Cisco Nexus 3164Q Firmware
Cisco Nexus 3172PQ/PQ-XL
Cisco Nexus 3172TQ-XL Firmware
Cisco Nexus 3232C
Cisco Nexus 3264C-E Firmware
Cisco Nexus 3264Q Firmware
Cisco Nexus 3408-S Firmware
Cisco Nexus 34180YC Firmware
Cisco Nexus 3432D-S Firmware
Cisco Nexus 3464C Firmware
Cisco Nexus 3524-x/xl
Cisco Nexus 3548-x/xl
Cisco Nexus 36180YC-R Firmware
Cisco Nexus 3636C-R Firmware
Cisco Nexus 7000
Cisco Nexus 7000
Cisco Nexus 7000
Cisco Nexus 7000 9-Slot Firmware
Cisco NX-OS Nexus 9000 Series
Cisco Nexus 92160YC Switch
Cisco Nexus 92300YC Firmware
Cisco Nexus 92304QC Switch
Cisco Nexus 92348GC-X Switch
Cisco Nexus 9236C Switch
Cisco Nexus 9272Q Switch
Cisco Nexus
Cisco Nexus 93108TC-EX-24 Firmware
Cisco Nexus 93108TC-FX Switch
Cisco Nexus 93108TC-FX Switch
Cisco Nexus 93108TC-FX3P Firmware
Cisco Nexus 93120TX Firmware
Cisco Nexus 93128 Firmware
Cisco Nexus 9316D-GX Firmware
Cisco Nexus 93180LC-EX Switch
Cisco Nexus 93180YC-EX-24
Cisco Nexus 93180YC-EX-24 Firmware
Cisco Nexus 93180YC-FX Firmware
Cisco Nexus 93180YC-FX-24 Firmware
Cisco Nexus 93180YC-FX3 Firmware
Cisco Nexus 93180YC-FX3S Firmware
Cisco Nexus 93216TC-FX2 Firmware
Cisco Nexus 93240YC-FX2 Firmware
Cisco Nexus 9332C Firmware
Cisco Nexus 9332PQ Firmware
Cisco Nexus 93360YC-FX2
Cisco Nexus 9336C-FX2 Firmware
Cisco Nexus 9336C-FX2-E Firmware
Cisco Nexus 9348GC-FXP Firmware
Cisco Nexus 93600CD-GX Firmware
Cisco Nexus 9364c-h1
Cisco Nexus 9364C-GX Firmware
Cisco Nexus 9372PX-E
Cisco Nexus 9372PX-E Firmware
Cisco Nexus 9372TX
Cisco Nexus 9372TX-E Switch
Cisco Nexus 9396PX Firmware
Cisco Nexus 9396TX Firmware
Cisco Nexus 9508

Remedy

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-mpls-oam-dos-sGO9x5GM

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-1588?

    CVE-2021-1588 has a high severity rating as it can allow unauthenticated remote attackers to cause a denial of service condition.

  • How do I fix CVE-2021-1588?

    To fix CVE-2021-1588, upgrade to a Cisco NX-OS version that is not affected by the vulnerability, as outlined in Cisco's security advisory.

  • Which Cisco NX-OS versions are affected by CVE-2021-1588?

    CVE-2021-1588 affects Cisco NX-OS 7.0(3)i7(9), 8.4(1), and 9.3(7).

  • Can CVE-2021-1588 be exploited locally?

    No, CVE-2021-1588 can only be exploited remotely by unauthenticated attackers.

  • What is the potential impact of CVE-2021-1588?

    The potential impact of CVE-2021-1588 is a denial of service, which may render affected devices unreachable.

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