Thanks nekrosoft13...Keystrokes, including passwords, can be sniffed when using Windows Terminal Server or the XP remote control feature. MS has rolled a fix silently into SP1 without making any public statement on this serious problem.
The cause of the keystroke
sniffing feature is a design mistake in Microsoft's Remote Desktop Protocol (RDP) which leaks information about the contents of encrypted packets through their checksums. This is because packets with the same plaintext have matching checksums throughout a particular session.
So if an attacker captures network traffic from an encrypted session it is possible to work out the keystrokes made by a user through rudimentary frequency analysis.
News source: The Reg (US)
View: The full story