C-sharp : Unsafe format string

The application uses an insecure format string. If formatting arguments come from an untrusted source, an attacker can disrupt the structure of the string or cause a buffer overflow, which leads to application crash or valuable data leak.

String format functions accept any number of arguments and can not determine how many arguments are passed in a particular call. If you pass fewer arguments than the format string provides, the missing data may be taken from the stack, which, in general, contains the data not related to the current call.