How can remove manky virus from SC7715 NAND

>>Boot downloaded.
12:37:57 > CPU TYPE:SC7715[7715A000]
>>Boot downloaded.
12:38:02 > Flash ID: 00AD00BC9055
12:38:02 > Flash Type:[Hyundai] NAND_HY27UT088G2A
12:38:02 > FLASH LEN:0x20000000
12:38:02 >