CVE-2026-20086: Cisco IOS XE Software

High severity, CVSS 8.6. EPSS: 0.4% chance of exploitation in the next 30 days.

A vulnerability in the processing of Control and Provisioning of Wireless Access Points (CAPWAP) packets of Cisco IOS XE Wireless Controller Software for the Catalyst CW9800 Family could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of a malformed CAPWAP packet. An attacker could exploit this vulnerability by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload unexpectedly, resulting in a DoS condition.

Affected products

• Cisco Cisco IOS XE Software: version 17.14.1 only; version 17.15.1 only; version 17.15.2 only; version 17.15.3 only; version 17.15.2b only; version 17.15.4 only; …

Published 2026-03-25. Last modified 2026-06-17.