A command injection vulnerability exists in the ToToLink A720R Router firmware V4.1.5cu.614B20230630 within the sysconf binary, specifically in the sub40BFA4 function that handles network interface reinitialization from '/var/system/linuxvlanreinit'. Input is only partially validated by checking the prefix of interface names, and is concatenated into shell commands executed via system() without escaping. An attacker with write access to this file can execute arbitrary commands on the device.

A stack buffer overflow exists in the ToToLink A720R Router firmware V4.1.5cu.614B20230630 within the sysconf binary (sub401EE0 function). The binary reads the /proc/stat file using fgets() into a local buffer and subsequently parses the line using sscanf() into a single-byte variable with the %s format specifier. Maliciously crafted /proc/stat content can overwrite adjacent stack memory, potentially allowing an attacker with filesystem write privileges to execute arbitrary code on the device.

A local stack-based buffer overflow vulnerability exists in the infostat.cgi and cstecgi.cgi binaries of ToToLink routers (A720R V4.1.5cu.614B20230630, LR1200GB V9.1.0u.6619B20230130, and NR1800X V9.1.0u.6681B20230703). Both programs parse the contents of /proc/net/arp using sscanf() with "%s" format specifiers into fixed-size stack buffers without length validation. Specifically, one function writes user-controlled data into a single-byte buffer, and the other into adjacent small arrays without bounds checking. An attacker who controls the contents of /proc/net/arp can trigger memory corruption, leading to denial of service or potential arbitrary code execution.

A command injection vulnerability exists in the ToToLink A720R Router firmware V4.1.5cu.614B20230630 within the cloudupdatecheck binary, specifically in the sub402414 function that handles cloud update parameters. User-supplied 'magicid' and 'url' values are directly concatenated into shell commands and executed via system() without any sanitization or escaping. An unauthenticated remote attacker can exploit this vulnerability to execute arbitrary commands on the device.