Multiple use-after-free vulnerabilities in OpenTTD 1.0.x before 1.0.5 allow (1) remote attackers to cause a denial of service (invalid write and daemon crash) by abruptly disconnecting during transmission of the map from the server, related to network/network_server.cpp; (2) remote attackers to cause a denial of service (invalid read and daemon crash) by abruptly disconnecting, related to network/network_server.cpp; and (3) remote servers to cause a denial of service (invalid read and application crash) by forcing a disconnection during the join process, related to network/network.cpp.