[Reverse] Headache

Type your comment> @job0 said:

Really enjoyed this challenge, lots of learning and a few headaches :slight_smile:

For me, it was getting over the first hump was the hardest. Afterwards the rest flows fairly naturally. I used mainly GDB and Ghidra.

Ghidra isn’t showing me any functions.

Solved but my head is on fire!

I found the function where there is the md5 o simply hex char sequence, and that is used in a function with best… ever… strings . is that the right function ?

Holy mother of ************* this was so ■■■■■■■ difficult. I learned so much from this though.

I tried to get flag but all of them fake.
If I run debug and enter the flag, result will “Login success!”; but I directly run script, it’s failed.
I tried to modify some instruction but error.
Please give me some hint!!!
Thanks so much!

Edit: Too many fake flags but I eventually found the right one. So headache…

Has anyone gotten Ida to run/debug this, it keeps giving me an error because it not a ‘standard’ executable. I think I understand how it was compiled… but that doesn’t help me run it

Did anybody use angr for solving this kind of challenge?

I’ve done all the lower points challenges but I’ve got no idea on where to start to do this one. Is there any good reference to study?

Finally got this one!!! Lots of headache for sure. But at the same time good learnings.

Man, I took way longer on this than I really needed to. Once I realized what was happening, and tread carefully, I knew right where to go. Good challenge!

I used mainly GDB and objdump for this. Also needed Capstone for some more analysis.

For anybody who’s still stuck, let me try to give some non-spoiler hints (if these count as spoilers, feel free to remove this):

  1. (GDB) Catchpoints may help you figure things out a bit.
  2. Read the description of the challenge, it’s important.

Done! Great challenge.

Can anyone help me out with this? I know what is messing up my debugging, but I can’t figure out where it is going after that…

Done!
IDA free did the trick

hii

i don’t understand how to break 0ld is gold.pdf challenge can any one help me ??

Use IDA finish this challenge.
But i don’t know how to use GDB to finish this task, can anybody give some idea to debug no debugging symbols file?

Type your comment> @vest12385 said:

Use IDA finish this challenge.
But i don’t know how to use GDB to finish this task, can anybody give some idea to debug no debugging symbols file?

@Chainmanner said:
Man, I took way longer on this than I really needed to. Once I realized what was happening, and tread carefully, I knew right where to go. Good challenge!

I used mainly GDB and objdump for this. Also needed Capstone for some more analysis.

For anybody who’s still stuck, let me try to give some non-spoiler hints (if these count as spoilers, feel free to remove this):

  1. (GDB) Catchpoints may help you figure things out a bit.
  2. Read the description of the challenge, it’s important.

Very useful. Thx.

Somehow the steps that work to obtain the flag in IDA don’t work with radare2. Can somebody explain why?

Hello, Is anybody else stuck in a part of code that seems to only acces and manipulate a particular adress in memory, i’m just starting to think that the main function didn’t load properly, i don’t know if it is for a particular antidebug mechanism that i haven’t seen or what can it be… :confused:

i got similar issue.bypass the ptrace anti-debug technique. am new to this known little gdb. some can help to fix the elf?