CVE-2023-20056: Cisco Access Point Software Denial of Service Vulnerability

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-03-23 · updated 2026-06-17
Weakness: CWE-78

Description

A vulnerability in the management CLI of Cisco access point (AP) software could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of commands supplied by the user. An attacker could exploit this vulnerability by authenticating to a device and submitting crafted input to the affected command. A successful exploit could allow the attacker to cause an affected device to reload spontaneously, resulting in a DoS condition.

Affected products

Cisco Mobility Express 1800 Access Point Series: before 17.9.0.135 — fixed in 17.9.0.135
Cisco IOS XE: before 16.12.8; from 17.1 before 17.3.6; from 17.4 before 17.6.5; from 17.7 before 17.9.2 — fixed in 16.12.8, 17.3.6, 17.6.5, 17.9.2
Cisco Wireless LAN Controller (WLC): before 8.10.183.0 — fixed in 8.10.183.0

How to fix

Upgrade to a fixed version: Cisco Mobility Express 1800 Access Point Series 17.9.0.135; Cisco IOS XE 16.12.8, 17.3.6, 17.6.5, 17.9.2; Cisco Wireless LAN Controller (WLC) 8.10.183.0. Check the vendor advisory for mitigations.

References

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