CVE-2021-1624 Cisco IOS XE Software Rate Limiting Network Address Translation Denial of Service Vulnerability

High 8.6 Published 23 Sep 2021 Updated 7 Nov 2024

Remote attackers can cause denial of service on Cisco IOS XE devices by exploiting a flaw in the Rate Limiting NAT feature.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2021-1624?

CVE-2021-1624 is a high-severity denial of service vulnerability in Cisco Ios Xe, published on 23 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Weakness: CWE-399

Which versions are affected by CVE-2021-1624?

It affects 1 product.

Products include Cisco Ios Xe.

How do I fix CVE-2021-1624?

No fix has been published for CVE-2021-1624 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-1624 being exploited?

There is no known exploitation of CVE-2021-1624 in the wild and no public exploit code.

All Cisco Ios Xe vulnerabilities

Sources

Also known as GHSA-xj7m-j8gx-jwq9.