Cisco IOS XE Software Rate Limiting Network Address Translation DoS (cisco-sa-ratenat-pYVLA7wM)

high Nessus Plugin ID 169453


The remote device is missing a vendor-supplied security patch


According to its self-reported version, Cisco IOS-XE Software is affected by a vulnerability.

- 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. (CVE-2021-1624)

Please see the included Cisco BID and Cisco Security Advisory for more information.


Upgrade to the relevant fixed version referenced in Cisco bug ID CSCvx37176

See Also

Plugin Details

Severity: High

ID: 169453

File Name: cisco-sa-ratenat-pYVLA7wM-iosxe.nasl

Version: 1.2

Type: combined

Family: CISCO

Published: 1/3/2023

Updated: 9/28/2023

Supported Sensors: Nessus

Risk Information


Risk Factor: Medium

Score: 4.4


Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2021-1624


Risk Factor: High

Base Score: 8.6

Temporal Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:cisco:ios_xe

Required KB Items: Host/Cisco/IOS-XE/Version

Exploit Ease: No known exploits are available

Patch Publication Date: 9/22/2021

Vulnerability Publication Date: 9/22/2021

Reference Information

CVE: CVE-2021-1624

CWE: 399

CISCO-SA: cisco-sa-ratenat-pYVLA7wM

IAVA: 2021-A-0441-S