1)Check the code with ghidra
2)Notice enc_hint and above it enc_flag ,
enc_flag XREF[2]: 004000c0(*),
_elfSectionHeaders::00000090(*)
00402000 e8 ?? E8h
00402001 ee ?? EEh
00402002 f9 ?? F9h
00402003 ef ?? EFh
00402004 e9 ?? E9h
00402005 d1 ?? D1h
00402006 d8 ?? D8h
00402007 99 ?? 99h
00402008 fc ?? FCh
00402009 f5 ?? F5h
0040200a c7 ?? C7h
0040200b 99 ?? 99h
0040200c f5 ?? F5h
0040200d eb ?? EBh
0040200e d9 ?? D9h
0040200f e7 ?? E7h
00402010 f5 ?? F5h
00402011 e8 ?? E8h
00402012 ee ?? EEh
00402013 d7 ?? D7h
enc_hint XREF[2]: entry:00401000(*),
entry:00401013(R)
00402014 e8 undefined1 E8h
3)Copy special from enc_flag
4)Decrypt with given key within the code : as it is a simple xor problem
do {
*pbVar3 = *pbVar2 ^ key;
pbVar2 = pbVar2 + 1;
pbVar3 = pbVar3 + 1;
lVar1 = lVar1 + -1;
} while (lVar1 != 0);