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11:26 PM 01/31/2019
Description
This is the first crackme i ever created, also the first piece of asm code i ever wrote, as you can take from the name, it grew from a hello-world example.
I still would rate it as difficulty 2 since most level 1 crackmes are kind of obvious to solve once you open them in some debugger.
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zer0sun on 7:06 AM 02/04/2019: Please enter your name: 1234
Hello 1234
Enter your Password: 6789
Great H4x0r Skillz!
use gdb to debug the program,'crackme' just compare the username & password with number 5
zer0sun on 8:58 AM 02/04/2019: as a beginer，this is great，tks~~
tanmaybhushan on 7:43 PM 02/12/2019: It has a bug or may be that was the intention, it loops over the length of password, not over the length of username.
Please enter your name: hello
Hello hello
Enter your Password: m
Great H4x0r Skillz!
Don't see any place to upload solution
Uzernem on 8:18 PM 02/12/2019: @zer0sun Don't post the solution in the comments, post it in the solution.
lala74 on 1:36 PM 08/11/2019: I don't see any place to upload solution so I post it here :D
After using gdb to disassemble the program, the function to verify the password is _start.l1
It takes the (length_password)th value of name + 5 and compares it with the last value of password
Ex: name: 1000000000, pass : 6, so the process will take the first value of name (length of pass = 1), it's 1, sum with 5 = 6 and the last value of pass is 6. They are equal so we break the program :D
OmniScientist on 11:33 PM 12/05/2019: I'm super beginner to this thing, I can fiddle with the binary with gdb but I don't know how to use gdb on the binary inside the zip file, so how could I use gdb in this case
mp on 10:08 AM 08/23/2020: Nice crack me for beginners. I would suggest resetting the color in _start.exit
Aether on 12:36 PM 11/19/2020: Nice crackme. I would suggest too to resetting the color in _start.exit
RobertoSpartan on 2:30 PM 12/26/2020: Nice example, no bugs but lot of distractions (for beginners at least).
there is a password length and not all input is OK, not gonna reveal it in this comment. Wurth trying.
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Solution by calo:
Simple but fun. Cheers.
Solution by vastopol:
write up, explanation, and disassembly included
Solution by alklazema:
A nice Caesar cipher puzzle. Thanks.
Solution by RobertoSpartan:
cracked with objdump, reading assembly code and finally edb debugger. (sudo apt install edb-debugger should do the trick on Ubuntu like systems)
Solution by Jenya:
nice i loved it