A cache buffer coupled to a page buffer includes: a first cache group and a second cache group corresponding to a first area and a second area of a memory cell array; a selector coupled to the first and second cache groups; and an input/output (I/O) controller coupled to the selector and configured to output data to the first and second cache groups or receive data input from the first and second cache groups. The selector: performs normal repair operation by transferring data received through a first data line to the first cache group and transferring data received through a second data line to the second cache group; performs cross repair operation by transferring data received through the first data line to the second cache group and transferring data received through the second data line to the first cache group.