An issue was discovered in e6y prboom-plus 2.5.1.5. There is a buffer overflow in client and server code responsible for handling received UDP packets, as demonstrated by I_SendPacket or I_SendPacketTo in i_network.c.
https://sourceforge.net/p/prboom-plus/bugs/253/
https://sourceforge.net/p/prboom-plus/bugs/252/
https://logicaltrust.net/blog/2019/10/prboom1.html
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00028.html
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00027.html