The uncompress_buffer function in src/server/simple_wml.cpp in Wesnoth before r33069 allows remote attackers to cause a denial of service via a large compressed WML document.
The read_game_map function in src/terrain_translation.cpp in Wesnoth before r32987 allows remote attackers to cause a denial of service (memory consumption and daemon hang) via a map with a large (1) width or (2) height.