CVE-2020-3560: Cisco Aironet Access Points UDP Flooding Denial of Service Vulnerability

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-09-24 · updated 2026-06-17
Weakness: CWE-400

Description

A vulnerability in Cisco Aironet Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) on an affected device. The vulnerability is due to improper resource management while processing specific packets. An attacker could exploit this vulnerability by sending a series of crafted UDP packets to a specific port on an affected device. A successful exploit could either allow the attacker to tear down the connection between the AP and the wireless LAN controller, resulting in the affected device not being able to process client traffic, or cause the vulnerable device to reload, triggering a DoS condition. After the attack, the affected device should automatically recover its normal functions without manual intervention.

Affected products

Cisco Access Points: before 16.12.4a — fixed in 16.12.4a
Cisco Mobility Express 1800 Access Point Series: 8.5(154.27), 8.8(125.0), 8.10(105.0), 8.10(105.4), 17.1.2.6, 17.1.2.9 (+1)
Cisco Business Access Points: from 10.0 before 10.1.1.0 — fixed in 10.1.1.0
Cisco Wireless Lan Controller: from 8.9 before 8.10.112.0 — fixed in 8.10.112.0
Cisco Wireless LAN Controller (WLC): before 8.5.161.0; from 8.6 before 8.8.130.0 — fixed in 8.5.161.0, 8.8.130.0

How to fix

Upgrade to a fixed version: Cisco Access Points 16.12.4a; Cisco Business Access Points 10.1.1.0; Cisco Wireless Lan Controller 8.10.112.0; Cisco Wireless LAN Controller (WLC) 8.5.161.0, 8.8.130.0. Check the vendor advisory for mitigations.

References

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