CVE-2021-1523

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.

Risk Information

Base Score

8.6

MODERATE

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS Score

Exploitation Probability

0.537

Associated Vulnerability

Vulnerability	OS Platform
Cisco Nexus 9000 Series Fabric Switches ACI Mode Queue Wedge Denial of Service Vulnerability For Cisco NX-OS System Software in ACI Mode	NCM
Missing Release of Resource after Effective Lifetime Vulnerability (CVE-2021-1523)	NCM

Patch Details

Click to see the patches provided by ManageEngine for this CVE

Patch ID	Patch Description
PATCH-1706155	Security Update for Cisco NX-OS System Software in ACI Mode 5.2(1)SV5(1.3b)

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234