[crypto] Flippin_Bank

Amazing challenge, definitely glad to have done this, thank you!!

I can modify the byte target successfully , but previous block gets messed up.
Any help?

python3 app.py
Traceback (most recent call last):
File “app.py”, line 7, in
from secret import FLAG
ModuleNotFoundError: No module named ‘secret’

:-/

Edit: I am stupid :slight_smile:
Edit 2: I am stuck hard as ■■■■… I think, I am at the last 20% of the challenge :neutral: Hope, someone could help me

Edit 3: FINALLY I got it! Thanks very much to my new best friends @alienum and @Civero for helping me and being very patient.
@P3t4: Very nice challenge! I learnt so much about python, crypto and how to use instances here :wink:

I think this challenge is hard for newbies in python and crypto, but it was very nice and I’m glad I solved it

Type your comment> @tXxc said:

python3 app.py
Traceback (most recent call last):
File “app.py”, line 7, in
from secret import FLAG
ModuleNotFoundError: No module named ‘secret’

:-/

Edit: I am stupid :slight_smile:
Edit 2: I am stuck hard as ■■■■… I think, I am at the last 20% of the challenge :neutral: Hope, someone could help me

Edit 3: FINALLY I got it! Thanks very much to my new best friends @alienum and @Civero for helping me and being very patient.
@P3t4: Very nice challenge! I learnt so much about python, crypto and how to use instances here :wink:

I think this challenge is hard for newbies in python and crypto, but it was very nice and I’m glad I solved it

Hey, I’m stuck on “no module named secret” and “Name FLAG not defined” too I’ve done pretty much everything else it’s just this bit… Can you please hint me to the right direction, am I missing any libraries or something :confused:

@hngrychckn412
Hey :slight_smile:
the module ‘secret’ and the variable ‘flag’ are used in CTFs to save the flag in an other module and not in the file, that you downloaded.
The script is running in an instance, you can start a new one within the challenge-menu in crpyto → Flippin Bank

Seen quite a few comments struggling with No module named 'flag':
If you wanna test locally, all you have to do is create a file called secret.py in the same folder you are trying to run app.py from, and in that file just type FLAG = "Anything really..".

This way, when app.py is trying to import the secret module, it will find something to import, and won’t throw an error. This way you can also define something to print, when you make your local instance print the flag. Hope this helps out someone :slight_smile:

Type your comment> @tXxc said:

python3 app.py
Traceback (most recent call last):
File “app.py”, line 7, in
from secret import FLAG
ModuleNotFoundError: No module named ‘secret’

:-/

Edit: I am stupid :slight_smile:
Edit 2: I am stuck hard as ■■■■… I think, I am at the last 20% of the challenge :neutral: Hope, someone could help me

Edit 3: FINALLY I got it! Thanks very much to my new best friends @alienum and @Civero for helping me and being very patient.
@P3t4: Very nice challenge! I learnt so much about python, crypto and how to use instances here :wink:

I think this challenge is hard for newbies in python and crypto, but it was very nice and I’m glad I solved it

can you help me out bro?

Hello, can someone send me a PM in order to give discuss this challenge and maybe give me some hints about it? Thanks

man I need nudge

Spoiler Removed

Never mind, i finally googled the name of the challenge with the encryption type and solved it pretty quick after that.

Hello, I’ve been struggling with the flipping for some time and still unable to know where to apply it without messing everything up. Could someone PM me or provide a hint? Thank you! :slight_smile:

Type your comment> @davihack said:

I can modify the byte target successfully , but previous block gets messed up.
Any help?

If an important block gets messed up, maybe check if you can mess up an unimportant one :wink:

Hi. Can someone help me, please? I run the file app.py but nothing appears. Why don’t appear the message “username:” ?

Type your comment> @cosmicgirl97 said:

Hi. Can someone help me, please? I run the file app.py but nothing appears. Why don’t appear the message “username:” ?

If you would like to run app.py locally please follow the steps below:

  1. Create a python script named ‘secret.py’ and assign to a variable named FLAG your fake flag.
  2. Execute on terminal: pip install pycrypto
  3. Execute on termina: python app.py

Hope this helps.

Hi, can anyone give me some help on this challenge, please?
I wrote a python script, that seems to work as I wish, but I cannot seem to retrieve the good output

Type your comment> @P3t4 said:

Type your comment> @cosmicgirl97 said:

Hi. Can someone help me, please? I run the file app.py but nothing appears. Why don’t appear the message “username:” ?

If you would like to run app.py locally please follow the steps below:

  1. Create a python script named ‘secret.py’ and assign to a variable named FLAG your fake flag.
  2. Execute on terminal: pip install pycrypto
  3. Execute on termina: python app.py

Hope this helps.

Thank you so much :slight_smile:

Type your comment> @lel1q said:

Hi, can anyone give me some help on this challenge, please?
I wrote a python script, that seems to work as I wish, but I cannot seem to retrieve the good output

Have you taken a look at which mode of operation is AES using?
You must exploit some vulnerability related to that.

Hello everyone
I need some helps / hints for this chall, I tried some staffs but nothing.
I think I understood how script and encryption works, I identified 3 blocks in the leaked ciphertext too but when I tried to modify a byte or when I encode the 2 last block myself , it doesn’t work …

anyone can help me please