| GautamGreat
40F7715CA1ED47726561
crackmes.one
64989B8FA31D85B3AE6F6E
https://pastebin.com/BzXmApH8
|
==> |
| I love working with Delphi compiled binaries.
Here I reversed the algo which is used to generate keys.
Written in Python3
import struct
import sys
def key_generator(name: str):
name = name.encode() # convert to bytes
const = 0x07FC
result = ""
for i in range(0, len(name) - 2): # need only first 4
ch = (const 8) ^ name[i]
result += "%02X" % ch
const = ((((ch * const) * 0xD201) & 0xFFFFFFFF) * 0x7F6A) & 0xFFFF
result += "%02X" % name[-2]
return result
if len(sys.argv) == 1:
print("Usage: Keygen.py ")
else:
print(key_generator(sys.argv[1])) |
==> |
| I'm able to get flag just by debugging.
flag{ThIs_vM_1s_n0t_EfF1ci4nT} |
==> |
| I think i over complicated things ;p
flag{vbScr1pt!_1s_n0t_s0_b4d?} |
==> |
| flag{y0_b0y_y0u_g0t_l0st!_aga1n??} |
==> |
| I packed it with a old upx, may e that is the problem.
There is nothing harmful in binary pure compiled with msvs 2013. |
==> |
| Level should be 2
data = [0x00001351, 0x0000135B, 0x00001356, 0x00001350, 0x0000134C, 0x0000137F, 0x00001303, 0x00001341, 0x00001304, 0x00001368, 0x00001303, 0x00001368, 0x00001359, 0x00001306, 0x00001354, 0x00001304, 0x00001368, 0x00001345, 0x00001304, 0x00001341, 0x00001304, 0x00001345, 0x00001344, 0x00001306, 0x00001359, 0x00001350, 0x00001368, 0x00001340, 0x00001303, 0x0000136E, 0x0000134A]
flag = ""
for i in data:
flag += chr(i ^ 0x1337)
print flag |
==> |
| it reminds me a ctf challenge
p**_ad*******_so****** |
==> |
| Nevermine I was trying it on python2, It is working pretty fast on Python3 |
==> |
| Hi,
@321test123, Thanks for testing my keygen me challenge. You were right there was a little bug in code of addition and multiplication. You keygen took so much time to generate keys, which is kinda unacceptable.
|
==> |
| I can't run it on my Windows7 x86 machine. |
==> |
| I dunno why but it crash in Windows 7 x86 |
==> |
| An awesome crackme challenge :D
I'm not spoiling the fun of others so here is MD5 hash of password
Password MD5 hash is E05E2327A8CEADA096724AFC802BBF7E |
==> |
| After little math I got a password it shows a message box but it seems encrypted.
one of the password is :
0148726828 |
==> |
| I don't know the difficulty, admins should decide it. |
==> |
| Seems problem with x32dbg, Use ollydbg instead, it is more stable. |
==> |
| Which debugger are you using? |
==> |
| The algo is perfectly reversable. Here is working key sets.
Name : GautamGreat
Key1 : UIKZK-Y6LN7-KMCKA-DPW7N-XTLQZ
Key2 : VQJZC-N4AX8-8E4QI-3BBEL-M2ZP6 |
==> |