RaphDev's PleaseCrackMe

Author:
RaphDev

Language:
C/C++

Upload:
2021-08-31 19:41

Download

Platform:
Unix/linux etc.

Difficulty:
1.6

Quality:
4.4

Arch:
x86-64

Downloads:
27

Writeups:
13

Comments:
24

Description

Tipp: there is no password-string in the code. The password will be created during the login-process

Comments (24)
Writeups (13)

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aziz00 on 2021-09-11 09:40: it been cracked, i have submitted the solution along with the source code. thanks a lot for this file.

aziz00 on 2021-09-11 21:04: [Click to reveal]

Anhkhoa on 2021-09-18 04:00: maybe I already have the code reversed but I don't know how to cut the extra characters at the end

matv201 on 2021-09-20 00:08: My first crackme! I believe I figured it out but can't get the binary to run. I renamed file with .exe and tried compatibility mode but still it says "cannot start or run due to incompatibility with 64-bit version of Windows". Any ideas?

matv201 on 2021-09-20 04:13: nvm, it is unix lol

RaphDev on 2021-09-23 15:47: @matv201 you cannot run it in windows it's a linux binary file

usernamechecksout on 2021-11-22 00:00: As a newbie on this site. Can i crack it by editing instructions? disturbing the flow of the program? or is there a flag?

RaphDev on 2021-11-26 22:11: usernamechecksout: you just have to reverse this binary and then find out how the algorithm works, that's it

tomg404 on 2021-11-29 00:23: Why does aaaaaa 1 bbbbbb work, but a 1 b doesn't? Can somebody explain?

KPia on 2021-12-12 19:49: Found a patch such as : if (iVar1 == 0) { puts("\nWrong password"); } else { puts("\nYou are succesfully logged in"); But I didn't really understood what was going on in the loop xD a = 0; while( true ) { a = x; b = strlen(usr); if (b

KPia on 2021-12-12 20:11: x = 0; while( true ) { a = (ulong)x; b = strlen(username); if (b

KPia on 2021-12-12 20:38: Sorry for messing up with the comments. tomg404: (a, 1, b) works. It's case sensitive. Ran the loop on my laptop and understood. Thx.

MM on 2022-01-03 19:55: Seems to me that there's a bug in the loop that goes through each char in Username and add up with the input number. The new string that this loop creates (in the stack position: rbp-0x50) is not terminated with NULL char, and strcmp function uses NULL char to know where's the end of both strings to compare. Because of this, the behavior ends up not deterministic

bond_u on 2022-02-21 18:53: Just set the breakpoint before taking the input password. examine the value of generated password by command x/s $rbp-0x50 and continue the program and enter the password stored in $rbp-0x50

3nnu1t3 on 2022-04-07 20:49: I was unable to use ltrace in this crackme, because it was likely compiled with -z now (see https://stackoverflow.com/questions/61394462/alternative-to-ltrace-that-works-on-binaries-linked-with-z-now/) I solved it using an alternative to ltrace that works with this type of file, is this cheating?? If you don't intend for us to use ltrace maybe you should say in the description RaphDev :)

andy on 2022-05-20 21:12: Nice and easy crackme. You can't enter a name with a space though, e.g "firstname surname"

Danofred on 2022-09-29 20:56: thanks brother for this little challenge

chris.dinozzi on 2023-04-14 14:27: fun challenge! :)

angz on 2023-04-19 11:17: very fun crackme! Absolutely funnier to go through this rather than the usual crackmes for beginners.

letuss004 on 2023-04-30 16:17: Beginner friendly, everyone should try :D

JNVIEGJ on 2023-10-05 20:27: [Click to reveal]

Mike_sp3c on 2024-02-23 23:02: Thanks! It helps to learn.

urohit011 on 2024-08-15 07:58: what's the password to unzip the downloaded zip file?

3M0oo0ry on 2025-12-25 13:41: Thanks! It helps to learn.

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Solution by Kryptoenix on 2021-09-05 19:59:
Great chall!

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Solution by taktufi on 2021-09-16 07:53:
The file contains code an explanation of solution. Best regards!

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Solution by estew on 2021-09-21 02:09:
This python3 file has comments explaining the logic behind the code based upon my analysis.

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Solution by ne0n_c4lic0 on 2021-09-29 17:09:
This is my first solution, hope someone finds it helpful. This binary was a blast.

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Solution by MANA624 on 2021-10-08 03:28:
My first solution, so hopefully this helps!

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Solution by St@rLord on 2021-11-20 23:07:
Second SRE project. Nice challenge!

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Solution by 7cherubin on 2022-07-17 19:13:

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Solution by MallNinja on 2023-02-18 12:01:
Tricky, just when you think you've got it, there's another layer

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Solution by chris.dinozzi on 2023-04-18 08:34:
Walkthrough using Ghidra static analysis and a keygen written in python3 :)

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Solution by lm337 on 2023-06-28 11:22:
A simple python3 script to generate password for any username/number combination

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Solution by 0chabyte on 2023-09-26 19:32:
First timing GDB

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Solution by HexHavoc on 2024-02-12 16:36:
The zip file contains solution and a python file to help with the solution as well :)

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Solution by 2k1-ArMlX on 2024-10-28 10:36:
The rar file contains solution....

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crackmes.one

crackmes.one

RaphDev's PleaseCrackMe