CVE-2021-1624

A vulnerability in the Rate Limiting Network Address Translation (NAT) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause high CPU utilization in the Cisco QuantumFlow Processor of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to mishandling of the rate limiting feature within the QuantumFlow Processor. An attacker could exploit this vulnerability by sending large amounts of traffic that would be subject to NAT and rate limiting through an affected device. A successful exploit could allow the attacker to cause the QuantumFlow Processor utilization to reach 100 percent on the affected device, resulting in a DoS condition.

• CWE-399

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ratenat-pYVLA7wMVendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ratenat-pYVLA7wMVendor Advisory

Published

Sep 23, 2021

Last Modified

Jun 17, 2026

Status

Modified

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