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This CVE record has been updated after NVD enrichment efforts were completed. Enrichment data supplied by the NVD may require amendment due to these changes.
Description
A 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.
Metrics
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CVE Modified by Cisco Systems, Inc.5/14/2024 3:59:01 AM
Action
Type
Old Value
New Value
CVE Modified by Cisco Systems, Inc.11/06/2023 10:28:30 PM
Action
Type
Old Value
New Value
Added
CVSS V3.1
Cisco Systems, Inc. AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Removed
CVSS V3
Cisco Systems, Inc. AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Initial Analysis by NIST9/02/2021 7:22:59 AM
Action
Type
Old Value
New Value
Added
CVSS V3.1
NIST AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Added
CVSS V2
NIST (AV:N/AC:L/Au:N/C:N/I:N/A:P)
Added
CWE
NIST CWE-772
Added
CPE Configuration
AND
OR
*cpe:2.3:o:cisco:nx-os:13.2\(3n\):*:*:*:*:*:*:*
*cpe:2.3:o:cisco:nx-os:14.2\(4i\):*:*:*:*:*:*:*
OR
cpe:2.3:h:cisco:nexus_93120tx:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_93128tx:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9332pq:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9372px:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9372px-e:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9372tx:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9372tx-e:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9396px:-:*:*:*:*:*:*:*
cpe:2.3:h:cisco:nexus_9396tx:-:*:*:*:*:*:*:*
Changed
Reference Type
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-queue-wedge-cLDDEfKF No Types Assigned
CVE Modified by Cisco Systems, Inc.8/25/2021 4:15:09 PM
Action
Type
Old Value
New Value
Changed
Description
A 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.
A 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.
Quick Info
CVE Dictionary Entry: CVE-2021-1523 NVD
Published Date: 08/25/2021 NVD
Last Modified: 06/16/2026
Source: Cisco Systems, Inc.