On OS X, when I install new software, the system pops up a dialogue window and asks me to input administrator password.
Is it possible that some malware pops up a window which is exactly the same as the real one, except that it stores the password and send it somewhere?
// Update
The password of my local machine would be useful:
1, when a hacker has already got into my system, and need my password to execute priviledged commands;
2, when a hacker has already got my account name, and only need a password to hack into my account. Many people use a single password in a number of places and the local password is a good guess for the account's password.