CVE-2026-129258: Tenda AC18 Firmware Upgrade upgrade data authenticity

A vulnerability was identified in Tenda AC18 15.03.05.05multi/15.03.05.19 Build 6318. Affected by this vulnerability is an unknown functionality of the file /cgi-bin/upgrade of the component Firmware Upgrade Handler. Such manipulation of the argument upgradeFile leads to insufficient verification of data authenticity. The attack may be launched remotely. The exploit is publicly available and might be used.