high
8.6
CWE
401
Advisory Published
Updated

CVE-2021-1387: Cisco NX-OS Software IPv6 Netstack Denial of Service Vulnerability

First published: Wed Feb 24 2021(Updated: )

A vulnerability in the network stack 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 exists because the software improperly releases resources when it processes certain IPv6 packets that are destined to an affected device. An attacker could exploit this vulnerability by sending multiple crafted IPv6 packets to an affected device. A successful exploit could cause the network stack to run out of available buffers, impairing operations of control plane and management plane protocols and resulting in a DoS condition. Manual intervention would be required to restore normal operations on the affected device. For more information about the impact of this vulnerability, see the Details section of this advisory.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco Unified Computing System software>=4.0<4.0\(4k\)
Cisco Unified Computing System software>=4.1<4.1\(1e\)
Cisco UCS 64108
Cisco UCS 6454 Fabric Interconnect
Cisco NX-OS=7.0\(0\)n1\(1\)
Cisco NX-OS=7.0\(1\)n1\(1\)
Cisco NX-OS=7.0\(2\)n1\(1\)
Cisco NX-OS=7.0\(3\)n1\(1\)
Cisco NX-OS=7.0\(4\)n1\(1\)
Cisco NX-OS=7.0\(4\)n1\(1a\)
Cisco NX-OS=7.0\(5\)n1\(1\)
Cisco NX-OS=7.0\(5\)n1\(1a\)
Cisco NX-OS=7.0\(6\)n1\(1\)
Cisco NX-OS=7.0\(6\)n1\(2s\)
Cisco NX-OS=7.0\(6\)n1\(3s\)
Cisco NX-OS=7.0\(6\)n1\(4s\)
Cisco NX-OS=7.0\(7\)n1\(1\)
Cisco NX-OS=7.0\(7\)n1\(1a\)
Cisco NX-OS=7.0\(7\)n1\(1b\)
Cisco NX-OS=7.0\(8\)n1\(1\)
Cisco NX-OS=7.0\(8\)n1\(1a\)
Cisco NX-OS=7.1\(0\)n1\(1\)
Cisco NX-OS=7.1\(0\)n1\(1a\)
Cisco NX-OS=7.1\(0\)n1\(1b\)
Cisco NX-OS=7.1\(1\)n1\(1\)
Cisco NX-OS=7.1\(1\)n1\(1a\)
Cisco NX-OS=7.1\(2\)n1\(1\)
Cisco NX-OS=7.1\(2\)n1\(1a\)
Cisco NX-OS=7.1\(3\)n1\(1\)
Cisco NX-OS=7.1\(3\)n1\(2\)
Cisco NX-OS=7.1\(3\)n1\(2a\)
Cisco NX-OS=7.1\(3\)n1\(3\)
Cisco NX-OS=7.1\(3\)n1\(4\)
Cisco NX-OS=7.1\(3\)n1\(5\)
Cisco NX-OS=7.1\(4\)n1\(1\)
Cisco NX-OS=7.1\(4\)n1\(1a\)
Cisco NX-OS=7.1\(4\)n1\(1c\)
Cisco NX-OS=7.1\(4\)n1\(1d\)
Cisco NX-OS=7.1\(5\)n1\(1\)
Cisco NX-OS=7.1\(5\)n1\(1b\)
Cisco NX-OS=7.2\(0\)n1\(1\)
Cisco NX-OS=7.2\(1\)n1\(1\)
Cisco NX-OS=7.3\(0\)n1\(1\)
Cisco NX-OS=7.3\(0\)n1\(1a\)
Cisco NX-OS=7.3\(0\)n1\(1b\)
Cisco NX-OS=7.3\(1\)n1\(1\)
Cisco NX-OS=7.3\(2\)n1\(1\)
Cisco NX-OS=7.3\(2\)n1\(1b\)
Cisco NX-OS=7.3\(2\)n1\(1c\)
Cisco NX-OS=7.3\(3\)n1\(1\)
Cisco NX-OS=7.3\(4\)n1\(1\)
Cisco NX-OS=7.3\(4\)n1\(1a\)
Cisco NX-OS=7.3\(5\)n1\(1\)
Cisco NX-OS=7.3\(6\)n1\(1\)
Cisco NX-OS=7.3\(6\)n1\(1a\)
Cisco NX-OS=7.3\(7\)n1\(1\)
Cisco NX-OS=7.3\(7\)n1\(1a\)
Cisco NX-OS=7.3\(7\)n1\(1b\)
Cisco Nexus 5548P Firmware
Cisco Nexus 5548UP Firmware
Cisco Nexus 5596T Firmware
Cisco Nexus 5596UP Firmware
Cisco 56128p
Cisco Nexus 5624Q Firmware
Cisco Nexus 5648Q Firmware
Cisco Nexus 5672UP-16G
Cisco Nexus 5672UP-16G Firmware
Cisco Nexus 5696Q Firmware
Cisco NX-OS=6.0\(2\)a3\(1\)
Cisco NX-OS=6.0\(2\)a3\(2\)
Cisco NX-OS=6.0\(2\)a3\(4\)
Cisco NX-OS=6.0\(2\)a4\(1\)
Cisco NX-OS=6.0\(2\)a4\(2\)
Cisco NX-OS=6.0\(2\)a4\(3\)
Cisco NX-OS=6.0\(2\)a4\(4\)
Cisco NX-OS=6.0\(2\)a4\(5\)
Cisco NX-OS=6.0\(2\)a4\(6\)
Cisco NX-OS=6.0\(2\)a6\(1\)
Cisco NX-OS=6.0\(2\)a6\(1a\)
Cisco NX-OS=6.0\(2\)a6\(2\)
Cisco NX-OS=6.0\(2\)a6\(2a\)
Cisco NX-OS=6.0\(2\)a6\(3\)
Cisco NX-OS=6.0\(2\)a6\(3a\)
Cisco NX-OS=6.0\(2\)a6\(4\)
Cisco NX-OS=6.0\(2\)a6\(4a\)
Cisco NX-OS=6.0\(2\)a6\(5\)
Cisco NX-OS=6.0\(2\)a6\(5a\)
Cisco NX-OS=6.0\(2\)a6\(5b\)
Cisco NX-OS=6.0\(2\)a6\(6\)
Cisco NX-OS=6.0\(2\)a6\(7\)
Cisco NX-OS=6.0\(2\)a6\(8\)
Cisco NX-OS=6.0\(2\)a7\(1\)
Cisco NX-OS=6.0\(2\)a7\(1a\)
Cisco NX-OS=6.0\(2\)a7\(2\)
Cisco NX-OS=6.0\(2\)a7\(2a\)
Cisco NX-OS=6.0\(2\)a8\(1\)
Cisco NX-OS=6.0\(2\)a8\(2\)
Cisco NX-OS=6.0\(2\)a8\(3\)
Cisco NX-OS=6.0\(2\)a8\(4\)
Cisco NX-OS=6.0\(2\)a8\(4a\)
Cisco NX-OS=6.0\(2\)a8\(5\)
Cisco NX-OS=6.0\(2\)a8\(6\)
Cisco NX-OS=6.0\(2\)a8\(7\)
Cisco NX-OS=6.0\(2\)a8\(7a\)
Cisco NX-OS=6.0\(2\)a8\(7b\)
Cisco NX-OS=6.0\(2\)a8\(8\)
Cisco NX-OS=6.0\(2\)a8\(9\)
Cisco NX-OS=6.0\(2\)a8\(10\)
Cisco NX-OS=6.0\(2\)a8\(10a\)
Cisco NX-OS=6.0\(2\)a8\(11\)
Cisco NX-OS=6.0\(2\)a8\(11a\)
Cisco NX-OS=6.0\(2\)a8\(11b\)
Cisco NX-OS=6.0\(2\)u2\(1\)
Cisco NX-OS=6.0\(2\)u2\(2\)
Cisco NX-OS=6.0\(2\)u2\(3\)
Cisco NX-OS=6.0\(2\)u2\(4\)
Cisco NX-OS=6.0\(2\)u2\(5\)
Cisco NX-OS=6.0\(2\)u2\(6\)
Cisco NX-OS=6.0\(2\)u3\(1\)
Cisco NX-OS=6.0\(2\)u3\(2\)
Cisco NX-OS=6.0\(2\)u3\(3\)
Cisco NX-OS=6.0\(2\)u3\(4\)
Cisco NX-OS=6.0\(2\)u3\(5\)
Cisco NX-OS=6.0\(2\)u3\(6\)
Cisco NX-OS=6.0\(2\)u3\(7\)
Cisco NX-OS=6.0\(2\)u3\(8\)
Cisco NX-OS=6.0\(2\)u3\(9\)
Cisco NX-OS=6.0\(2\)u4\(1\)
Cisco NX-OS=6.0\(2\)u4\(2\)
Cisco NX-OS=6.0\(2\)u4\(3\)
Cisco NX-OS=6.0\(2\)u4\(4\)
Cisco NX-OS=6.0\(2\)u5\(1\)
Cisco NX-OS=6.0\(2\)u5\(2\)
Cisco NX-OS=6.0\(2\)u5\(3\)
Cisco NX-OS=6.0\(2\)u5\(4\)
Cisco NX-OS=6.0\(2\)u6\(1\)
Cisco NX-OS=6.0\(2\)u6\(1a\)
Cisco NX-OS=6.0\(2\)u6\(2\)
Cisco NX-OS=6.0\(2\)u6\(2a\)
Cisco NX-OS=6.0\(2\)u6\(3\)
Cisco NX-OS=6.0\(2\)u6\(3a\)
Cisco NX-OS=6.0\(2\)u6\(4\)
Cisco NX-OS=6.0\(2\)u6\(4a\)
Cisco NX-OS=6.0\(2\)u6\(5\)
Cisco NX-OS=6.0\(2\)u6\(5a\)
Cisco NX-OS=6.0\(2\)u6\(5b\)
Cisco NX-OS=6.0\(2\)u6\(5c\)
Cisco NX-OS=6.0\(2\)u6\(6\)
Cisco NX-OS=6.0\(2\)u6\(7\)
Cisco NX-OS=6.0\(2\)u6\(8\)
Cisco NX-OS=6.0\(2\)u6\(9\)
Cisco NX-OS=6.0\(2\)u6\(10\)
Cisco NX-OS=6.0\(2\)u6\(10a\)
Cisco NX-OS=7.0\(3\)f3\(1\)
Cisco NX-OS=7.0\(3\)f3\(2\)
Cisco NX-OS=7.0\(3\)f3\(3\)
Cisco NX-OS=7.0\(3\)f3\(3a\)
Cisco NX-OS=7.0\(3\)f3\(3c\)
Cisco NX-OS=7.0\(3\)f3\(4\)
Cisco NX-OS=7.0\(3\)f3\(5\)
Cisco NX-OS=7.0\(3\)i2\(1\)
Cisco NX-OS=7.0\(3\)i2\(1a\)
Cisco NX-OS=7.0\(3\)i2\(2\)
Cisco NX-OS=7.0\(3\)i2\(2a\)
Cisco NX-OS=7.0\(3\)i2\(2b\)
Cisco NX-OS=7.0\(3\)i2\(2c\)
Cisco NX-OS=7.0\(3\)i2\(2d\)
Cisco NX-OS=7.0\(3\)i2\(2e\)
Cisco NX-OS=7.0\(3\)i2\(2r\)
Cisco NX-OS=7.0\(3\)i2\(2s\)
Cisco NX-OS=7.0\(3\)i2\(2v\)
Cisco NX-OS=7.0\(3\)i2\(2w\)
Cisco NX-OS=7.0\(3\)i2\(2x\)
Cisco NX-OS=7.0\(3\)i2\(2y\)
Cisco NX-OS=7.0\(3\)i2\(3\)
Cisco NX-OS=7.0\(3\)i2\(4\)
Cisco NX-OS=7.0\(3\)i2\(5\)
Cisco NX-OS=7.0\(3\)i3\(1\)
Cisco NX-OS=7.0\(3\)i4\(1\)
Cisco NX-OS=7.0\(3\)i4\(1t\)
Cisco NX-OS=7.0\(3\)i4\(2\)
Cisco NX-OS=7.0\(3\)i4\(3\)
Cisco NX-OS=7.0\(3\)i4\(4\)
Cisco NX-OS=7.0\(3\)i4\(5\)
Cisco NX-OS=7.0\(3\)i4\(6\)
Cisco NX-OS=7.0\(3\)i4\(6t\)
Cisco NX-OS=7.0\(3\)i4\(7\)
Cisco NX-OS=7.0\(3\)i4\(8\)
Cisco NX-OS=7.0\(3\)i4\(8a\)
Cisco NX-OS=7.0\(3\)i4\(8b\)
Cisco NX-OS=7.0\(3\)i4\(8z\)
Cisco NX-OS=7.0\(3\)i4\(9\)
Cisco NX-OS=7.0\(3\)i5\(1\)
Cisco NX-OS=7.0\(3\)i5\(2\)
Cisco NX-OS=7.0\(3\)i5\(3\)
Cisco NX-OS=7.0\(3\)i5\(3a\)
Cisco NX-OS=7.0\(3\)i5\(3b\)
Cisco NX-OS=7.0\(3\)i6\(1\)
Cisco NX-OS=7.0\(3\)i6\(2\)
Cisco NX-OS=7.0\(3\)i7\(1\)
Cisco NX-OS=7.0\(3\)i7\(2\)
Cisco NX-OS=7.0\(3\)i7\(3\)
Cisco NX-OS=7.0\(3\)i7\(3z\)
Cisco NX-OS=7.0\(3\)i7\(4\)
Cisco NX-OS=7.0\(3\)i7\(5\)
Cisco NX-OS=7.0\(3\)i7\(5a\)
Cisco NX-OS=7.0\(3\)i7\(6\)
Cisco NX-OS=7.0\(3\)i7\(6z\)
Cisco NX-OS=7.0\(3\)i7\(7\)
Cisco NX-OS=7.0\(3\)i7\(8\)
Cisco NX-OS=7.0\(3\)ic4\(4\)
Cisco NX-OS=7.0\(3\)im7\(2\)
Cisco Nexus 3016Q Firmware
Cisco Nexus 3016Q Firmware
Cisco Nexus 3048 Firmware
Cisco Nexus 3064 Firmware
Cisco Nexus 3064
Cisco Nexus 3064
Cisco Nexus 3064x
Cisco Nexus 3064
Cisco Nexus 3064-X Firmware
Cisco Nexus 3100V Firmware
Cisco Nexus 3100-Z firmware
Cisco Nexus 3100V Firmware
Cisco Nexus 31108PC-V Firmware
Cisco Nexus 31108PV-V Firmware
Cisco Nexus 31108TC-V Firmware
Cisco Nexus 31128PQ
Cisco Nexus 3132C-Z Firmware
Cisco Nexus 3132Q-XL
Cisco Nexus 3132Q-V Firmware
Cisco Nexus 3132Q-X/3132Q-XL
Cisco Nexus 3132Q-XL Firmware
Cisco Nexus 3164Q Firmware
Cisco Nexus 3172 Firmware
Cisco Nexus 3172PQ/PQ-XL
Cisco Nexus 3172PQ-XL Firmware
Cisco Nexus 3172TQ Firmware
Cisco Nexus 3172TQ-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 34200YC-SM Firmware
Cisco Nexus 3432D-S Firmware
Cisco Nexus 3464C Firmware
Cisco Nexus 3524-xl
Cisco Nexus 3524-xl
Cisco Nexus 3524-XL Firmware
Cisco Nexus 3548-X/XL Firmware
Cisco Nexus 3548-X/XL
Cisco Nexus 3548-X/XL
Cisco Nexus 36180YC-R Firmware
Cisco Nexus 3636C-R Firmware
Cisco Nexus 6001 Firmware
Cisco Nexus 6001P Firmware
Cisco Nexus 6001T Firmware
Cisco Nexus 6004 Firmware
Cisco Nexus 6004X Firmware
Cisco NX-OS=7.2\(0\)d1\(1\)
Cisco NX-OS=7.2\(1\)d1\(1\)
Cisco NX-OS=7.2\(2\)d1\(1\)
Cisco NX-OS=7.2\(2\)d1\(2\)
Cisco NX-OS=7.2\(2\)d1\(3\)
Cisco NX-OS=7.2\(2\)d1\(4\)
Cisco NX-OS=7.3\(0\)d1\(1\)
Cisco NX-OS=7.3\(0\)dx\(1\)
Cisco NX-OS=7.3\(1\)d1\(1\)
Cisco NX-OS=7.3\(2\)d1\(1\)
Cisco NX-OS=7.3\(2\)d1\(1d\)
Cisco NX-OS=7.3\(2\)d1\(2\)
Cisco NX-OS=7.3\(2\)d1\(3\)
Cisco NX-OS=7.3\(2\)d1\(3a\)
Cisco NX-OS=7.3\(3\)d1\(1\)
Cisco NX-OS=7.3\(4\)d1\(1\)
Cisco NX-OS=7.3\(5\)d1\(1\)
Cisco NX-OS=7.3\(6\)d1\(1\)
Cisco NX-OS=8.0\(1\)
Cisco NX-OS=8.1\(1\)
Cisco NX-OS=8.1\(2\)
Cisco NX-OS=8.1\(2a\)
Cisco NX-OS=8.2\(1\)
Cisco NX-OS=8.2\(2\)
Cisco NX-OS=8.2\(3\)
Cisco NX-OS=8.2\(4\)
Cisco NX-OS=8.2\(5\)
Cisco NX-OS=8.3\(1\)
Cisco NX-OS=8.3\(2\)
Cisco NX-OS=8.4\(1\)
Cisco NX-OS=8.4\(2\)
Cisco Nexus 7000
Cisco Nexus 7004 Firmware
Cisco Nexus 7009 Firmware
Cisco Nexus 7010 Firmware
Cisco Nexus 7018 Firmware
Cisco Nexus 7700 series
Cisco Nexus 7702 firmware
Cisco Nexus 7706 firmware
Cisco Nexus 7710 Firmware
Cisco Nexus 7718 firmware
Cisco NX-OS=7.0\(3\)f1\(1\)
Cisco NX-OS=7.0\(3\)f2\(1\)
Cisco NX-OS=7.0\(3\)f2\(2\)
Cisco NX-OS=7.0\(3\)ia7\(1\)
Cisco NX-OS=7.0\(3\)ia7\(2\)
Cisco NX-OS=7.0\(3\)im3\(1\)
Cisco NX-OS=7.0\(3\)im3\(2\)
Cisco NX-OS=7.0\(3\)im3\(2a\)
Cisco NX-OS=7.0\(3\)im3\(2b\)
Cisco NX-OS=7.0\(3\)im3\(3\)
Cisco NX-OS Nexus 9000 Series
Cisco Nexus 92160YC Switch
Cisco Nexus 92160YC-X Firmware
Cisco Nexus 9221C Firmware
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 93128 Firmware
Cisco Nexus 9316D-GX Firmware
Cisco Nexus 93180LC-EX Switch
Cisco Nexus 93180TC-EX Firmware
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 N9336PQ
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 9500R Firmware
Cisco Nexus 9504 firmware
Cisco Nexus 9508
Cisco Nexus 9516 firmware

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-1387?

    The severity of CVE-2021-1387 is classified as high due to its potential to cause a denial of service condition.

  • How do I fix CVE-2021-1387?

    To fix CVE-2021-1387, update your Cisco NX-OS Software to a version that addresses this vulnerability.

  • Which versions of Cisco NX-OS are affected by CVE-2021-1387?

    CVE-2021-1387 affects multiple versions of Cisco NX-OS including 7.0(0)n1(1) through 8.4(2).

  • Can CVE-2021-1387 be exploited remotely?

    Yes, CVE-2021-1387 can be exploited by unauthenticated remote attackers.

  • What are the possible consequences of CVE-2021-1387?

    The consequences of CVE-2021-1387 include a denial of service condition, causing affected devices to become unresponsive.

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