SuSE Security Advisory - gdm prior to 2.0beta4 allows remote root compromise. Gdm is the GNOME replacment for xdm, handling graphical console and network logins. The gdm code, that process' logins over the network, could be tricked into writing data from the network right into the stack. This condition exists while gdm is running with root privileges and before the user is authenticated. Other distributions are affected as well. SuSE security site here.
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