CVE-2019-1920 Cisco IOS Access Points Software 802.11r Fast Transition Denial of Service Vulnerability

High 7.4 Published 17 Jul 2019 Updated 21 Nov 2024

An unauthenticated adjacent attacker can cause a denial of service on Cisco IOS Access Points by sending crafted 802.11r Fast Transition authentication requests.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: None listed

What is CVE-2019-1920?

CVE-2019-1920 is a high-severity denial of service vulnerability in Cisco Aironet Access Point Software, published on 17 Jul 2019. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A vulnerability in the 802.11r Fast Transition (FT) implementation for Cisco IOS Access Points (APs) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected interface. The vulnerability is due to a lack of complete error handling condition for client authentication requests sent to a targeted interface configured for FT. An attacker could exploit this vulnerability by sending crafted authentication request traffic to the targeted interface, causing the device to restart unexpectedly.

Weakness: CWE-20

Which versions are affected by CVE-2019-1920?

It affects 4 products.

Products include Cisco Access Points, Cisco Aironet 3700e Firmware, Cisco Aironet 3700i Firmware, Cisco Aironet 3700p Firmware.

How do I fix CVE-2019-1920?

No fix has been published for CVE-2019-1920 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-2019-1920 being exploited?

There is no known exploitation of CVE-2019-1920 in the wild and no public exploit code.

Sources

Also known as GHSA-4w9g-6vm8-cmqg.