The CClient::ProcessServerPacket method in engine/client/client.cpp in Teeworlds before 0.6.4 allows remote servers to write to arbitrary physical memory locations and possibly execute arbitrary code via vectors involving snap handling.
https://www.teeworlds.com/?page=news&id=12086
https://security.gentoo.org/glsa/201705-13
https://github.com/teeworlds/teeworlds/commit/ff254722a2683867fcb3e67569ffd36226c4bc62
http://www.securityfocus.com/bid/94381