Enhance OS security by restricting privileges of vulnerable application

Restricting vulnerable process and its file I/O behaviors is important for securing an embedded device against intrusions, malware infection and information leakage. On embedded device like Smart TV, user can connect to internet using Web Browser process and can download many applications and games. These applications or games may have viruses or vulnerable code. If attacker with root privilege is able to launch new process (using fork () in Linux system) then the downloaded virus program will also get root privileges and hence vulnerable application with root user privileges may corrupt the whole system. This paper proposes a new method to protect the system from this kind of security threats. For experiment and result verification, proposed method uses LSM framework and TOMOYO module. It implements the LSM hook in fork/exec system call path to control the privileges of vulnerable application/binary. Android addresses this problem by writing a wrapper to fork system call in their framework, which modifies credential of new process. However they leave security hole, if application directly calls fork () system call.