Crypt::ScryptKDF versions through 0.010 for Perl uses insecure random number source when no CSPRNG module is available. The random_bytes function fell back to using the built-in rand() function when none of the Perl modules Crypt::PRNG, Crypt::OpenSSL::Random, Net::SSLeay, Crypt::Random, or Bytes::Random::Secure were available.