Information Flow Control and Taint Analysis with Dependence Graphs

• For critical system, formal approaches are needed. One is (static) information flow control which analyzes the software to check if it conforms to some security policy. An example is noninterference: secret information does not influence the publicly observable behavior of a system. • Many informal approaches can be subsumed under bug detection. A violation of some security policy can be regarded as a bug and therefore many bug detection approaches do some kind of taint analysis. Data from untrusted sources (e.g. the user) is tainted and is not allowed to reach exploitable functions like system calls vulnerable to buffer overruns.