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CVE-2021-1586

HIGH severity · CVSS 8.6 · CWE-345
8.6CVSS HIGH

Summary

A vulnerability in the Multi-Pod or Multi-Site network configurations for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to unexpectedly restart the device, resulting in a denial of service (DoS) condition. This vulnerability exists because TCP traffic sent to a specific port on an affected device is not properly sanitized. An attacker could exploit this vulnerability by sending crafted TCP data to a specific port that is listening on a public-facing IP address for the Multi-Pod or Multi-Site configuration. A successful exploit could allow the attacker to cause the device to restart unexpectedly, resulting in a DoS condition.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactNone
Availability impactHigh
Exploit probability (EPSS)2%

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

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-tcp-dos-YXukt6gM ↗