CVE-2021-1523

Summary

CVECVE-2021-1523
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-08-25 19:15:00 UTC
Updated2023-11-07 03:28:00 UTC
DescriptionA vulnerability in Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, remote attacker to cause a queue wedge on a leaf switch, which could result in critical control plane traffic to the device being dropped. This could result in one or more leaf switches being removed from the fabric. This vulnerability is due to mishandling of ingress TCP traffic to a specific port. An attacker could exploit this vulnerability by sending a stream of TCP packets to a specific port on a Switched Virtual Interface (SVI) configured on the device. A successful exploit could allow the attacker to cause a specific packet queue to queue network buffers but never process them, leading to an eventual queue wedge. This could cause control plane traffic to be dropped, resulting in a denial of service (DoS) condition where the leaf switches are unavailable. Note: This vulnerability requires a manual intervention to power-cycle the device to recover.

Risk And Classification

Problem Types: CWE-772

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Hardware Cisco Nexus 93120tx - All All All
Hardware Cisco Nexus 93128tx - All All All
Hardware Cisco Nexus 9332pq - All All All
Hardware Cisco Nexus 9372px - All All All
Hardware Cisco Nexus 9372px-e - All All All
Hardware Cisco Nexus 9372tx - All All All
Hardware Cisco Nexus 9372tx-e - All All All
Hardware Cisco Nexus 9396px - All All All
Hardware Cisco Nexus 9396tx - All All All
Operating System Cisco Nx-os 13.2\(3n\) All All All
Operating System Cisco Nx-os 14.2\(4i\) All All All

References

ReferenceSourceLinkTags
Cisco Nexus 9000 Series Fabric Switches ACI Mode Queue Wedge Denial of Service Vulnerability CISCO tools.cisco.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 317021 Cisco Nexus 9000 Series Fabric Switches ACI Mode Queue Wedge Denial of Service Vulnerability (cisco-sa-n9kaci-queue-wedge-cLDDEfKF)

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