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

Severity: high (CVSS 7.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-07-17 · updated 2026-06-17
Weakness: CWE-20

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.

Affected products

Cisco Access Points: before 8.2.170.0; from 8.3 before 8.3.150.0; from 8.4 before 8.5.131.0; from 8.6 before 8.8.100.0 — fixed in 8.2.170.0, 8.3.150.0, 8.5.131.0, 8.8.100.0
Cisco Aironet 3700E Firmware: 15.3(3)jc14, 15.3(3)jd6
Cisco Aironet 3700I Firmware: 15.3(3)jc14, 15.3(3)jd6
Cisco Aironet 3700P Firmware: 15.3(3)jc14, 15.3(3)jd6

How to fix

Upgrade to a fixed version: Cisco Access Points 8.2.170.0, 8.3.150.0, 8.5.131.0, 8.8.100.0. Check the vendor advisory for mitigations.

References

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