raxer's Simple Crackme

Author:
raxer

Language:
C/C++

Upload:
2020-06-02 02:04

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Platform:
Windows

Difficulty:
2.0

Quality:
4.3

Arch:
x86-64

Downloads:
19

Size:
1.55 KB

Writeups:
3

Comments:
15

Description

Beginner friendly, no bytepatching. CRT was disabled for the most part so that it's easier to follow the code during static analysis.

Comments (15)
Writeups (3)

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korsader on 2020-06-07 15:23: [Click to reveal]

korsader on 2020-06-07 15:54: how can I decrypt my password???

ItzzMeGrrr on 2020-06-10 03:23: How do you decrypt this "BGOTHXIY"? Can anyone help?

jeffli6789 on 2020-06-10 08:45: code starting at 0x400418 is both executed as code and later used as the index into the string "BGOTHXIY". Nice one, thx!

flatdietsoda on 2020-06-10 13:06: whats the password?

struggle on 2020-06-15 03:36: [Click to reveal]

Parad0x13 on 2020-06-15 11:43: [Click to reveal]

juansacco on 2020-07-06 09:40: [Click to reveal]

Senken on 2020-07-08 17:49: SPOILER ALERT! Im pretty close, i know that the password consists of 13 letters from the following set: {B,G,O,T,H,X,I,Y} and that the password is made from getting the N th letter of the string bgothxiy (if b is letter 0) where n = *((_BYTE *)&loc_C00418 + v0) & 7 (

ghsi10 on 2020-08-08 19:28: great one! thanks :)

ghsi10 on 2020-08-08 19:29: @Senken, loc_C00418 is code but there is value for each opcode :)

Slaktaren on 2020-09-27 10:31: [Click to reveal]

Astronaut on 2020-11-15 01:16: As a newbie, I haven't wasted my time on decryption. Only two NOPs worked for all passwords.

Onyx_Pl01t on 2021-12-28 20:22: i'm pretty sure i am close to the answer but i am not getting the right answer. As i have understood, there is a data been called at 0x400418. I do not know what is it storing. I know the length of the password is 13 and it involves the use of these letters namely B,G,O,T,H,X,I,Y. The only thing i am not understanding is that 'decrypting' process. it is referring to the address of the unknown_var at 0x400418 which is of type BYTE and it is adding it to loop's counter.Then, it goes through a Bitwise AND with 7. The result is then used for indexing in the buffer ,holding "BGOTHYIX", so as to retrieve a specific letter from it and it compares it with the first letter of our password input and so on until reaching the 13th letter. For example, if *((_BYTE)&data_0x400418 + loop_counter) & 7) = 0 Then, the first letter of our input should be buffer[0] which is "B" and it goes on till finision. i would like to know how you decrypt the buffer since i am not understanding it well.

lookkattme on 2023-01-30 12:10: [Click to reveal]

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Solution by ismaelvazquezjr on 2020-06-12 16:26:
Text file.

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Solution by 7cherubin on 2022-07-21 09:06:

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Solution by Endst on 2022-08-05 17:58:
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crackmes.one

crackmes.one

raxer's Simple Crackme