engine/server.cpp in Sauerbraten 2006_02_28, as derived from the Cube engine, allows remote attackers to cause a denial of service (segmentation fault) via a client that does not completely join the game and times out, which results in a null pointer dereference.
Sauerbraten 2006_02_28, as derived from the Cube engine, allows remote attackers to cause a denial of service (client exit) by forcing the server to change to a map (ogz) file whose name contains ".." sequences and has a certain length that prevents the addition of the ".ogz" extension.