cert-msc51-cpp¶

This check flags all pseudo-random number engines, engine adaptor instantiations and srand() when initialized or seeded with default argument, constant expression or any user-configurable type. Pseudo-random number engines seeded with a predictable value may cause vulnerabilities e.g. in security protocols. This is a CERT security rule, see MSC51-CPP. Ensure your random number generator is properly seeded and MSC32-C. Properly seed pseudorandom number generators.

Examples:

void foo() {
  std::mt19937 engine1; // Diagnose, always generate the same sequence
  std::mt19937 engine2(1); // Diagnose
  engine1.seed(); // Diagnose
  engine2.seed(1); // Diagnose

  std::time_t t;
  engine1.seed(std::time(&t)); // Diagnose, system time might be controlled by user

  int x = atoi(argv[1]);
  std::mt19937 engine3(x);  // Will not warn
}