Sep
15

Leet More 2010 Strange Cipher writeup

Decrypt this “UPDYUFFRPY\TDDSUITF\R\FARTTITYGPPF\/YSGDFYAAO:DF/TA\IAGR:A//DR/T”. ctf.ifmo.ru:5555 If we connect to the service and try to encrypt \x00, \x01, \x02, \x03, \x04, we can notice that only first two bytes and the last one change: [ GDOPU/SIIR\TDPAFYGDA/:S/EIT\\FS/OA:PRYS/DOIOTIS/GUPPYPS/GIGPUSS\ ] [ GFOPU/SIIR\TDPAFYGDA/:S/EIT\\FS/OA:PRYS/DOIOTIS/GUPPYPS/GIGPUSSE ] [ GGOPU/SIIR\TDPAFYGDA/:S/EIT\\FS/OA:PRYS/DOIOTIS/GUPPYPS/GIGPUSSR ] [ ::OPU/SIIR\TDPAFYGDA/:S/EIT\\FS/OA:PRYS/DOIOTIS/GUPPYPS/GIGPUSST ] There are 16 different chars, so a good idea is to… Continue reading »