The traceroute function on the TP-Link TL-WR840N v4 router with firmware through 0.9.1 3.16 is vulnerable to remote code execution via a crafted payload in an IP address input field.

TP-Link TL-WR840N v5 00000005 devices allow XSS via the network name. The attacker must log into the router by breaking the password and going to the admin login page by THC-HYDRA to get the network name. With an XSS payload, the network name changed automatically and the internet connection was disconnected. All the users become disconnected from the internet.