A keylogger can be a device hidden on the keyboard cable and broadcasting every single key.
A keylogger can be a hidden program injected by some mean (say a downloaded package).
Such situations do not need an attacker present on the machine.
Posted Nov 10, 2011 20:44 UTC (Thu) by felixfix (subscriber, #242)
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That's quibbling. In those cases, the attacker is the keylogger, not the person who installed it, and it is on your machine, as was the installer when they installed the keylogger.