In nqptp-message-handlers.c in nqptp before 1.2.3, crafted packets received on the control port could crash the program.
https://github.com/mikebrady/nqptp/releases/tag/1.2.4
https://github.com/mikebrady/nqptp/releases/tag/1.2.3
https://github.com/mikebrady/nqptp/commit/b24789982d5cc067ecf6e8f3352b701d177530ec