In 2.6, when you execute a mongodump/mongorestore with auth info, the password will not be displayed when you issue a "ps -ef" command to list the running process.

See attachment mongodump-output-2.6

In 3.0.6/3.2, however, the password will be displayed when doing "ps -ef" command.

See attachment mongodump-output-3.0

This would allow other users to be able to learn the mongodb password.