App - System

Hi all. I’ve scoured the source up and down for days but the only BSS anywhere in the code is the handler array in msg.c and there’s absolutely no way to overflow it as there’s no user-facing code that can affect it at all. Even if there was, the add_handler function has all the appropriate bounds checking in it. Where am I going wrong? Is the challenge incorrectly named and I should instead look at the stack variables? Can anybody at least give me a hint regarding which source file has the vulnerability so I know where to look?