CVE-2026-4565: Tenda AC21 Firmware

High severity, CVSS 8.8. EPSS: 1% chance of exploitation in the next 30 days.

A vulnerability was detected in Tenda AC21 16.03.08.16. Impacted is the function formSetQosBand of the file /goform/SetNetControlList. Performing a manipulation of the argument list results in buffer overflow. The attack can be initiated remotely. The exploit is now public and may be used.

Affected products

• Tenda AC21 Firmware: version 16.03.08.16 only

Published 2026-03-23. Last modified 2026-06-17.