Godot Engine version All versions prior to 2.1.5, all 3.0 versions prior to 3.0.6. contains a Signed/unsigned comparison, wrong buffer size chackes, integer overflow, missing padding initialization vulnerability in (De)Serialization functions (core/io/marshalls.cpp) that can result in DoS (packet of death), possible leak of uninitialized memory. This attack appear to be exploitable via A malformed packet is received over the network by a Godot application that uses built-in serialization (e.g. game server, or game client). Could be triggered by multiplayer opponent. This vulnerability appears to have been fixed in 2.1.5, 3.0.6, master branch after commit feaf03421dda0213382b51aff07bd5a96b29487b.
https://godotengine.org/article/maintenance-release-godot-3-0-6
https://godotengine.org/article/maintenance-release-godot-2-1-5