How about checking the addresses of those "data items"?
The address of the variable is 0x20000130 which is within valid address range of RAM. But the address pointed by BFAR is 0x28000130 which is out of the range. It appears that an extra bit is getting set. Also this fault does not occur every single time. In one board, the fault occurs within 15 mins after power on. While in another board, the fault occurs after more than 1 hour.