CVE-2021-31756: Tenda AC11 Firmware

Critical severity, CVSS 9.8. EPSS: 2.9% chance of exploitation in the next 30 days.

An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. A stack buffer overflow vulnerability in /gofrom/setwanType allows attackers to execute arbitrary code on the system via a crafted post request. This occurs when input vector controlled by malicious attack get copied to the stack variable.

Affected products

• Tenda AC11 Firmware: up to and including 02.03.01.104_cn

Published 2021-05-07. Last modified 2026-06-17.