TerraMaster TOS before 4.1.29 has invalid parameter checking that leads to code injection as root. This is a dynamic class method invocation vulnerability in include/exportUser.php, in which an attacker can trigger a call to the exec method with (for example) OS commands in the opt parameter.
View the template here CVE-2020-15568.yaml
References:
https://github.com/n0bugz/CVE-2020-15568