Any kind of typical C memory corruption that you can think of that fails to validate the buffer sizes that you give as parameters.

WebAssembly memory access bytecodes only do bounds checking of the linear memory block that gets allocated to the module.

You then do your own memory management taking subsets from that memory block and assigning it to the respective internal heap allocations or global memory blocks.

So you just need to have a couple of structs or C string/arrays, living alongside each other and overwrite one of them by writing too much data due to miscalculations of the memory segment holding the data.