Linux X Windows flaw lets intruders in
Perhaps more of the 'experienced' linux users, already know about this, but figured to post it, to help those who hadn't disabled it, or knew about it.
From:
ExtremeTech
Linux X Windows flaw lets intruders in
Many distributions of Linux (and some other UNIX-like operating system distributions) appear to be misconfigured, by default, to allow root logins from across the network. The flaw, which was fixed by Caldera in its own software in 1999 but was recently discovered to be widespread, is in the configuration of X Windows; it allows anyone to obtain a remote console and mount a password guessing attack.
According to the advisory at the second link below, Mandrake Linux 8.0, SuSe Linux 7.2, and Irix 6.2 are affected. Solaris is partially vulnerable; it allows access but will not allow direct root logins. Red Hat 7.2 and Caldera are not vulnerable. Other UNIX-like operating system distributions may or may not be vulnerable.
Claims that this is a "Back Orifice for UNIX" are overblown, but it's still a good idea to disable remote X Windows logins from across the Internet. (The advisory at the second link below describes how to do this.) Secure Shell (SSH), which provides encryption and better authentication, can still be used if you must run X Windows sessions from afar.