CVE-2025-9791: Tenda AC20 Firmware

Critical severity, CVSS 9.8. EPSS: 0.9% chance of exploitation in the next 30 days.

A weakness has been identified in Tenda AC20 16.03.08.05. This vulnerability affects unknown code of the file /goform/fromAdvSetMacMtuWan. This manipulation of the argument wanMTU causes stack-based buffer overflow. Remote exploitation of the attack is possible. The exploit has been made available to the public and could be exploited.

Affected products

• Tenda AC20 Firmware: version 16.03.08.5 only

Published 2025-09-01. Last modified 2026-09-26.