Inteno routers have a JUCI ACL misconfiguration that allows the "user" account to read files, write to files, and add root SSH keys via JSON commands to ubus. (Exploitation is sometimes easy because the "user" password might be "user" or might match the Wi-Fi key.)
Inteno iopsys 2.0-3.14 and 4.0 devices allow remote authenticated users to execute arbitrary OS commands by modifying the leasetrigger field in the odhcpd configuration to specify an arbitrary program, as demonstrated by a program located on an SMB share. This issue existed because the /etc/uci-defaults directory was not being used to secure the OpenWrt configuration.