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crypto

Grab your Jisho

As the title suggested, I grabbed my Jisho (jisho.org) and pasted the first "word" in.

In the side panel I saw 20-8-5 for the stroke numbers, which I immidiately recognised as A1Z26 cipher for 'THE'.

The characters were encoded into kanji with an equivalent stroke number.

I continued manual decryption until I identified the plaintext as http://www.gutenberg.org/files/45723/45723-h/45723-h.htm .

At this point I wrote a quick script to match kanji to letters 1:1 in one paragraph, and use replace on the whole text.

This was much faster, and once I had decrypted 10 or so paragraphs like this grepping for rgb yielded the encrypted flag - 璧技丩忄鰏叒讞鸞鸚鱺鑱磒夢洶飳勊淩鼱殆鸝钁厵鬱. However, some kanji had values above 26.

I struggled with this for a while before trying to just extend them on the ASCII table, which worked!

Flag: rgbctf{~|~yominikui~|~} (meaning: illegible)

Shakespeare Play, Lost (and found!)

Each line has two numbers. I guessed that the numbers were encoding

line of play, character of line

So, just write a script to parse the data, then grab the appropriate lines and characters, then concatenate to get the flag.

Flag: rgbCTF{itsanrgbtreeeeeee!}

(rgbctf/crypto/e.md)

I Love Rainbows

So you're given a bunch of md5 and sha256 hashes, after cracking the hashes, you get a bunch of characters, slap em together and you get the flag

Flag: rgbCTF{4lw4ys_us3_s4lt_wh3n_h4shing}

Adequate Encryption Standard

Let's break down the encryption step by step.

It splits the plaintext into padded blocks of 8. It also expands the key using a key expansion function so that the key is as long as the amount of blocks. The key expansion function causes a drastic loss in size of the keyspace by using modular exponentiation that is not with primitive roots and is modulus a composite(256), which would allow for more optimised bruteforce, but I didn't use this in the end. For each block, it goes through 8 rounds. In each round: 1. Take the current ciphertext. Put it through the sbox(basically a substitution table) 2. Then, put it through the pbox, essentially shuffling the binary based on a pre-determined pbox of indexes. 3. Xor every byte of the current block with the current byte of the expanded key

The sbox and the pbox are things we can easily invert. The only real "encryption" step is the xor bit.

The problem is that unlike normal AES where the key is expanded into 11 keys of the same length of the blocks, in here the key is expanded into essentially 1 byte keys. For each block, for each round, it will keep XORing with the same current byte of the key.

Essentially, we can bruteforce each byte of the key until we get printable values, as the encryption reduces the key in each block to one byte, and this one byte can be bruteforced.

I wrote inversion functions to handle the sbox and pbox, then simply bruted the one byte expanded key of each block until I got a printable value. We can concatenate the decrypted blocks to get the flag,

Script:

Flag: rgbCTF{brut3_f0rc3_is_4LW4YS_th3_4nsw3r(but_with_0ptimiz4ti0ns)}

Occasionally Tested Protocol

Looking at the code, we can see it uses random.randint to generate the one time pad.

The thing that is most of note is that it seeds python's random generator using the current time.

Not only this, it prints out the first 10 random numbers outputted by the generator by doing random.randint(5, 10000) and printing the output 10 times.

We can record the time shortly after we connect to the server.

Chances are, we won't have the exact right value.

rubikcbc

im aware there is a module for this but: 1. idk how to use it 2. i dont want my effort to go to waste (since i made my own cube manipulator) 3. i dont like installing one time modules cus they clog up space

since it was just cbc i just had to map it to a cube and reverse the scramble then xorred it to get a pdf file

i spent too long fixing bugs with the xor process and how bytes are handled i also spent too long fixing bugs of my cube program

found a qr code in pdf and...

Script:

rgbCTF{!IP_over_Avian_Carriers_with_QoS!}

N-AES

So, at first this seems literally impossible.

The rand_block function takes a random 1 byte seed(initialising it to the output of os.urandom(1) if the argument isnt given) and then generates a 16-byte random block from this.

The encryption is simple - given a stream of seed bytes and a plaintext, iterate through the seed bytes.

On each byte, set the current ciphertext variable to the current ciphertext variable encrypted with the key generated by the random block that is create using rand_block(cur_byte_of_seed)

Finally, the challenge is generated like so. A random base64 string is generated using urandom, then encrypted in the algorithm. We get the base64 of the encryption.

def gen_chall(text):
    text = pad(text, BLOCK_SIZE)
    for i in range(128):
        text = AES.new(rand_block(), AES.MODE_ECB).encrypt(text) # VULN

    return b64encode(text)

So, what's so fishy about this?

Notice no argument is passed to rand_block, it simply gets a rand block and encrypts 128 times.

The argument is supposed to be os.urandom(1) by default, right? The problem is, everytime you call the function with no argument, the os.urandom(1) isnt regenerated. Instead, the value is first generated when the function is defined and then set to that again and again and again.

Long story short - chall is generated with the same key 128 times. Since it's os.urandom(1), we'll only have to bruteforce 256 possible keys. That can be done easily, and we can check if we've decrypted correctly by checking if the padding matches.

From there, we can simply enter the decrypted ciphertext.

^ script prints out the needed base64, you'll have to manually enter it into the prompt to get the flag from there

Flag: rgbCTF{i_d0nt_7hink_7his_d03s_wh47_y0u_7hink_i7_d03s}

Shakespeare Play, Lost (and found!)

Each line has two numbers. I guessed that the numbers were encoding

line of play, character of line

So, just write a script to parse the data, then grab the appropriate lines and characters, then concatenate to get the flag.

play = """A long lost play about trees, written exclusively by Shakespeare for RGBSec.

Romeo, apparently a rapidly changing multicolored tree.
Hamlet, a person who can't make up his mind.


                    Act I: Colorful Tree.

                    Scene I: Fast-changing Tree.

[Enter Hamlet and Romeo]

Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
[Exeunt]
"""
nums = """33, 20
71, 5
43, 142
60, 150
73, 312
78, 66
15, 22
12, 115
29, 18
51, 147
45, 68
34, 14
54, 126
15, 48
3, 4
60, 126
45, 77
13, 69"""
nums = nums.split('\n')
nums = [[int(x) for x in y.split(', ')] for y in nums]
play = play.split('\n')
flag = ''
for pair in nums:
    flag += play[pair[0]][pair[1]]
print(flag)

Flag: rgbCTF{itsanrgbtreeeeeee!}

play = """A long lost play about trees, written exclusively by Shakespeare for RGBSec.

Romeo, apparently a rapidly changing multicolored tree.
Hamlet, a person who can't make up his mind.


                    Act I: Colorful Tree.

                    Scene I: Fast-changing Tree.

[Enter Hamlet and Romeo]

Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a red green blue red green tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a red tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green blue tree! You are as lovely as the sum of a  tree and thyself! Speak your mind!
Hamlet: You are nothing! You are a red green blue red green tree! You are as lovely as the sum of a red green blue red tree and thyself! You are as lovely as the sum of a red green blue tree and thyself! You are as lovely as the sum of a  tree and thyself! Speak your mind!
[Exeunt]
"""
nums = """33, 20
71, 5
43, 142
60, 150
73, 312
78, 66
15, 22
12, 115
29, 18
51, 147
45, 68
34, 14
54, 126
15, 48
3, 4
60, 126
45, 77
13, 69"""
nums = nums.split('\n')
nums = [[int(x) for x in y.split(', ')] for y in nums]
play = play.split('\n')
flag = ''
for pair in nums:
    flag += play[pair[0]][pair[1]]
print(flag)

Adequate Encryption Standard

Let's break down the encryption step by step.

The sbox and the pbox are things we can easily invert. The only real "encryption" step is the xor bit.

Essentially, we can bruteforce each byte of the key until we get printable values, as the encryption reduces the key in each block to one byte, and this one byte can be bruteforced.

Script:

Flag: rgbCTF{brut3_f0rc3_is_4LW4YS_th3_4nsw3r(but_with_0ptimiz4ti0ns)}

from Crypto.Util.number import *
import string
BLOCK_SIZE = 8
ROUNDS = 8
import base64
sbox = [111, 161, 71, 136, 68, 69, 31, 0, 145, 237, 169, 115, 16, 20, 22, 82, 138, 183, 232, 95, 244, 163, 64, 229, 224, 104, 231, 61, 121, 152, 97, 50, 74, 96, 247, 144, 194, 86, 186, 234, 99, 122, 46, 18, 215, 168, 173, 188, 41, 243, 219, 203, 141, 21, 171, 57, 116, 178, 233, 210, 184, 253, 151, 48, 206, 250, 133, 44, 59, 147, 137, 66, 52, 75, 187, 129, 225, 209, 191, 92, 238, 127, 241, 25, 160, 9, 170, 13, 157, 45, 205, 196, 28, 146, 142, 150, 17, 39, 24, 80, 118, 6, 32, 93, 11, 216, 220, 100, 85, 112, 222, 226, 126, 197, 180, 34, 182, 37, 148, 70, 78, 201, 236, 81, 62, 42, 193, 67, 8, 164, 43, 252, 166, 221, 208, 176, 235, 149, 109, 63, 103, 223, 65, 56, 140, 255, 218, 54, 153, 2, 228, 1, 240, 248, 246, 110, 156, 60, 227, 207, 254, 51, 174, 79, 128, 155, 251, 242, 177, 135, 230, 154, 179, 15, 189, 143, 130, 27, 107, 211, 30, 105, 19, 134, 124, 125, 245, 76, 204, 12, 26, 38, 40, 131, 117, 87, 114, 213, 212, 102, 195, 101, 55, 10, 47, 120, 200, 217, 88, 83, 36, 198, 249, 192, 23, 94, 181, 73, 185, 172, 165, 58, 53, 202, 106, 5, 7, 175, 89, 72, 90, 14, 162, 158, 119, 139, 77, 108, 190, 91, 29, 49, 159, 33, 113, 214, 4, 123, 199, 167, 35, 239, 84, 3, 132, 98]
pbox = [39, 20, 18, 62, 4, 60, 19, 43, 33, 6, 51, 61, 40, 35, 47, 16, 23, 58, 31, 53, 28, 55, 54, 30, 17, 42, 34, 45, 49, 13, 46, 0, 26, 2, 8, 3, 11, 48, 63, 36, 37, 7, 32, 5, 27, 59, 29, 44, 14, 56, 21, 22, 12, 52, 57, 41, 10, 1, 24, 38, 50, 15, 9, 25]
def to_blocks(in_bytes: bytes) -> list:
    return [in_bytes[i:i + BLOCK_SIZE] for i in range(0, len(in_bytes), BLOCK_SIZE)]
def invert_sbox(in_bytes: bytes):
    return bytes([sbox.index(b) for b in in_bytes])
def invert_pbox(in_bytes: bytes):
    permuted = ''.join(bin(b)[2:].zfill(8) for b in in_bytes)
    binary = list('-'*BLOCK_SIZE*8)
    for i in range(len(permuted)):
        binary[pbox[i]] = permuted[i]
    binary = ''.join(binary)
    return long_to_bytes(int(binary,2))
def decwithbyte(block,byte):
    for _ in range(ROUNDS):
        block = bytearray(block)
        for i in range(len(block)):
            block[i] ^= byte
        block = invert_pbox(block)
        block = invert_sbox(block)
    return block
enc = base64.b64decode(b"hQWYogqLXUO+rePyWkNlBlaAX47/2dCeLFMLrmPKcYRLYZgFuqRC7EtwX4DRtG31XY4az+yOvJJ/pwWR0/J9gg==")
enc = to_blocks(enc)
flagregex = string.printable
flag = ''
for block in enc:
    for i in range(256):
        try:
            response = decwithbyte(block,i)
            response = response.decode()
            if all(x in flagregex for x in response):
                flag += response
                break
        except:
            pass
print(flag)

rubikcbc

since it was just cbc i just had to map it to a cube and reverse the scramble then xorred it to get a pdf file

i spent too long fixing bugs with the xor process and how bytes are handled i also spent too long fixing bugs of my cube program

found a qr code in pdf and...

Script:

'''
so uhhh orange top green front

   OOO
   OOO
   OOO
YYYWWWGGGBBB - form LRFB
YYYWWWGGGBBB
YYYWWWGGGBBB
   RRR
   RRR
   RRR

   OOO
   OOO
   YYY
YYRWWWOGGBBB
YYRWWWOGGBBB
YYRWWWOGGBBB
   GGG
   RRR
   RRR

   WWW
   WWW
   WWW
RRRRRGOOOYYY
YYYRRGGGGOOO
YYYRRGGGGOOO

BYY
YWY
ORG

RRGYBBYOOGGGRROBBBWOOGGGRGWOOOBBBRRWWYWWYWRWY
'''

facestring = "WWWWWWWWWRRRBBBOOOGGGRRRBBBOOOGGGRRRBBBOOOGGGYYYYYYYYY"

def format(a):
    out = ""
    a = a.replace("'","22")
    for i in a.split(" "):
        out += (i[0] + " ")*len(i)
    out = out[:-1]
    return out


def nice(a):
    for i in range(3):
        print("   "+a[i*3:i*3+3])
    for i in range(3):
        print(a[i*12+9:i*12+21])
    for i in range(3):
        print("   "+a[i*3+45:i*3+48])

def strface(a):
    new = [[["" for _ in range(3)] for _ in range(3)] for _ in range(6)]
    for i,j in enumerate(a[:9]):
        new[0][i//3][i%3] = j
    for i,j in enumerate(a[-9:]):
        new[5][i//3][i%3] = j
    mid = a[9:-9]
    for i in range(36):
        new[(i//3)%4+1][i//12][i%3] = mid[i]
    return new

def facestr(a):
    new = ""
    for i in a[0]:
        new += "".join(i)
    for i in range(3):
        for j in a[1:-1]:
            new += "".join(j[i])
    for i in a[-1]:
        new += "".join(i)
    return new

def bfacestr(a):
    new = []
    for i in a[0]:
        new += i
    for i in range(3):
        for j in a[1:-1]:
            new += j[i]
    for i in a[-1]:
        new += i
    return new

print(strface(facestring))
print(facestr(strface(facestring)))

def r(face , n = 1):
    for i in range(n):
        face = [list(x) for x in zip(*face[::-1])]
    return face

def shift(faces, nums):
    new = [x[:] for x in faces]
    newnums = nums[-1:] + nums[:-1]
    for i in range(4):
        new[newnums[i]][0] = faces[nums[i]][0]
    return new

def spin(faces,a):
    if a == 0:
        return faces
    if a == 1:
        return [r(faces[1]),r(faces[5]),r(faces[2]),r(faces[0]),r(faces[4],3),r(faces[3])]
    if a == 2:
        return [faces[2],r(faces[1],3),faces[5],r(faces[3]),r(faces[0],2),r(faces[4],2)]
    if a == 3:
        for i in range(3):
            faces = spin(faces,1)
        return faces
    if a == 4:
        for i in range(3):
            faces = spin(faces,2)
        return faces
    if a == 5:
        for i in range(2):
            faces = spin(faces,2)
        return faces

def turn(faces,a):
    b = ["U","L","F","R","B","D"].index(a)
    new_faces = spin(faces,b)

    new_faces[0] = r(new_faces[0])
    new_faces = shift(new_faces,[1,2,3,4])


    for i in range(3):
            new_faces = spin(new_faces,b)

    return new_faces

turns = "F' D F L' F U R' B2 U' D' L U2 D F2 L2 B2 L2 D"
turns = format(turns)
print(turns)
IV = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuv"

with open("enc_","rb") as f:
    kek = f.read()
    f.close()

kek2 = [kek[i*54:i*54+54] for i in range(len(kek)//54)]

out = b""

for kek3 in kek2:
    cube = strface(kek3)
    for i in turns.split(" "):
        cube = turn(cube,i)

    pp1 = bfacestr(cube)
    pp2 = bytes([_a ^ _b for _a, _b in zip(pp1, IV)])
    out += pp2

    IV = kek3

#print(out)

with open("out","wb") as f:
    f.write(out)
    f.close()

rgbCTF{!IP_over_Avian_Carriers_with_QoS!}

from Crypto.Util.number import *
import string
BLOCK_SIZE = 8
ROUNDS = 8
import base64
sbox = [111, 161, 71, 136, 68, 69, 31, 0, 145, 237, 169, 115, 16, 20, 22, 82, 138, 183, 232, 95, 244, 163, 64, 229, 224, 104, 231, 61, 121, 152, 97, 50, 74, 96, 247, 144, 194, 86, 186, 234, 99, 122, 46, 18, 215, 168, 173, 188, 41, 243, 219, 203, 141, 21, 171, 57, 116, 178, 233, 210, 184, 253, 151, 48, 206, 250, 133, 44, 59, 147, 137, 66, 52, 75, 187, 129, 225, 209, 191, 92, 238, 127, 241, 25, 160, 9, 170, 13, 157, 45, 205, 196, 28, 146, 142, 150, 17, 39, 24, 80, 118, 6, 32, 93, 11, 216, 220, 100, 85, 112, 222, 226, 126, 197, 180, 34, 182, 37, 148, 70, 78, 201, 236, 81, 62, 42, 193, 67, 8, 164, 43, 252, 166, 221, 208, 176, 235, 149, 109, 63, 103, 223, 65, 56, 140, 255, 218, 54, 153, 2, 228, 1, 240, 248, 246, 110, 156, 60, 227, 207, 254, 51, 174, 79, 128, 155, 251, 242, 177, 135, 230, 154, 179, 15, 189, 143, 130, 27, 107, 211, 30, 105, 19, 134, 124, 125, 245, 76, 204, 12, 26, 38, 40, 131, 117, 87, 114, 213, 212, 102, 195, 101, 55, 10, 47, 120, 200, 217, 88, 83, 36, 198, 249, 192, 23, 94, 181, 73, 185, 172, 165, 58, 53, 202, 106, 5, 7, 175, 89, 72, 90, 14, 162, 158, 119, 139, 77, 108, 190, 91, 29, 49, 159, 33, 113, 214, 4, 123, 199, 167, 35, 239, 84, 3, 132, 98]
pbox = [39, 20, 18, 62, 4, 60, 19, 43, 33, 6, 51, 61, 40, 35, 47, 16, 23, 58, 31, 53, 28, 55, 54, 30, 17, 42, 34, 45, 49, 13, 46, 0, 26, 2, 8, 3, 11, 48, 63, 36, 37, 7, 32, 5, 27, 59, 29, 44, 14, 56, 21, 22, 12, 52, 57, 41, 10, 1, 24, 38, 50, 15, 9, 25]
def to_blocks(in_bytes: bytes) -> list:
    return [in_bytes[i:i + BLOCK_SIZE] for i in range(0, len(in_bytes), BLOCK_SIZE)]
def invert_sbox(in_bytes: bytes):
    return bytes([sbox.index(b) for b in in_bytes])
def invert_pbox(in_bytes: bytes):
    permuted = ''.join(bin(b)[2:].zfill(8) for b in in_bytes)
    binary = list('-'*BLOCK_SIZE*8)
    for i in range(len(permuted)):
        binary[pbox[i]] = permuted[i]
    binary = ''.join(binary)
    return long_to_bytes(int(binary,2))
def decwithbyte(block,byte):
    for _ in range(ROUNDS):
        block = bytearray(block)
        for i in range(len(block)):
            block[i] ^= byte
        block = invert_pbox(block)
        block = invert_sbox(block)
    return block
enc = base64.b64decode(b"hQWYogqLXUO+rePyWkNlBlaAX47/2dCeLFMLrmPKcYRLYZgFuqRC7EtwX4DRtG31XY4az+yOvJJ/pwWR0/J9gg==")
enc = to_blocks(enc)
flagregex = string.printable
flag = ''
for block in enc:
    for i in range(256):
        try:
            response = decwithbyte(block,i)
            response = response.decode()
            if all(x in flagregex for x in response):
                flag += response
                break
        except:
            pass
print(flag)

'''
so uhhh orange top green front

   OOO
   OOO
   OOO
YYYWWWGGGBBB - form LRFB
YYYWWWGGGBBB
YYYWWWGGGBBB
   RRR
   RRR
   RRR

   OOO
   OOO
   YYY
YYRWWWOGGBBB
YYRWWWOGGBBB
YYRWWWOGGBBB
   GGG
   RRR
   RRR

   WWW
   WWW
   WWW
RRRRRGOOOYYY
YYYRRGGGGOOO
YYYRRGGGGOOO

BYY
YWY
ORG

RRGYBBYOOGGGRROBBBWOOGGGRGWOOOBBBRRWWYWWYWRWY
'''

facestring = "WWWWWWWWWRRRBBBOOOGGGRRRBBBOOOGGGRRRBBBOOOGGGYYYYYYYYY"

def format(a):
    out = ""
    a = a.replace("'","22")
    for i in a.split(" "):
        out += (i[0] + " ")*len(i)
    out = out[:-1]
    return out


def nice(a):
    for i in range(3):
        print("   "+a[i*3:i*3+3])
    for i in range(3):
        print(a[i*12+9:i*12+21])
    for i in range(3):
        print("   "+a[i*3+45:i*3+48])

def strface(a):
    new = [[["" for _ in range(3)] for _ in range(3)] for _ in range(6)]
    for i,j in enumerate(a[:9]):
        new[0][i//3][i%3] = j
    for i,j in enumerate(a[-9:]):
        new[5][i//3][i%3] = j
    mid = a[9:-9]
    for i in range(36):
        new[(i//3)%4+1][i//12][i%3] = mid[i]
    return new

def facestr(a):
    new = ""
    for i in a[0]:
        new += "".join(i)
    for i in range(3):
        for j in a[1:-1]:
            new += "".join(j[i])
    for i in a[-1]:
        new += "".join(i)
    return new

def bfacestr(a):
    new = []
    for i in a[0]:
        new += i
    for i in range(3):
        for j in a[1:-1]:
            new += j[i]
    for i in a[-1]:
        new += i
    return new

print(strface(facestring))
print(facestr(strface(facestring)))

def r(face , n = 1):
    for i in range(n):
        face = [list(x) for x in zip(*face[::-1])]
    return face

def shift(faces, nums):
    new = [x[:] for x in faces]
    newnums = nums[-1:] + nums[:-1]
    for i in range(4):
        new[newnums[i]][0] = faces[nums[i]][0]
    return new

def spin(faces,a):
    if a == 0:
        return faces
    if a == 1:
        return [r(faces[1]),r(faces[5]),r(faces[2]),r(faces[0]),r(faces[4],3),r(faces[3])]
    if a == 2:
        return [faces[2],r(faces[1],3),faces[5],r(faces[3]),r(faces[0],2),r(faces[4],2)]
    if a == 3:
        for i in range(3):
            faces = spin(faces,1)
        return faces
    if a == 4:
        for i in range(3):
            faces = spin(faces,2)
        return faces
    if a == 5:
        for i in range(2):
            faces = spin(faces,2)
        return faces

def turn(faces,a):
    b = ["U","L","F","R","B","D"].index(a)
    new_faces = spin(faces,b)

    new_faces[0] = r(new_faces[0])
    new_faces = shift(new_faces,[1,2,3,4])


    for i in range(3):
            new_faces = spin(new_faces,b)

    return new_faces

turns = "F' D F L' F U R' B2 U' D' L U2 D F2 L2 B2 L2 D"
turns = format(turns)
print(turns)
IV = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuv"

with open("enc_","rb") as f:
    kek = f.read()
    f.close()

kek2 = [kek[i*54:i*54+54] for i in range(len(kek)//54)]

out = b""

for kek3 in kek2:
    cube = strface(kek3)
    for i in turns.split(" "):
        cube = turn(cube,i)

    pp1 = bfacestr(cube)
    pp2 = bytes([_a ^ _b for _a, _b in zip(pp1, IV)])
    out += pp2

    IV = kek3

#print(out)

with open("out","wb") as f:
    f.write(out)
    f.close()

N-AES

So, at first this seems literally impossible.

The rand_block function takes a random 1 byte seed(initialising it to the output of os.urandom(1) if the argument isnt given) and then generates a 16-byte random block from this.

The encryption is simple - given a stream of seed bytes and a plaintext, iterate through the seed bytes.

On each byte, set the current ciphertext variable to the current ciphertext variable encrypted with the key generated by the random block that is create using rand_block(cur_byte_of_seed)

Finally, the challenge is generated like so. A random base64 string is generated using urandom, then encrypted in the algorithm. We get the base64 of the encryption.

def gen_chall(text):
    text = pad(text, BLOCK_SIZE)
    for i in range(128):
        text = AES.new(rand_block(), AES.MODE_ECB).encrypt(text) # VULN

    return b64encode(text)

So, what's so fishy about this?

Notice no argument is passed to rand_block, it simply gets a rand block and encrypts 128 times.

From there, we can simply enter the decrypted ciphertext.

^ script prints out the needed base64, you'll have to manually enter it into the prompt to get the flag from there

crypto

Grab your Jisho

hashtagFlag: rgbctf{~|~yominikui~|~} (meaning: illegible)

Shakespeare Play, Lost (and found!)

hashtagFlag: rgbCTF{itsanrgbtreeeeeee!}

(rgbctf/crypto/e.md)

I Love Rainbows

hashtagFlag: rgbCTF{4lw4ys_us3_s4lt_wh3n_h4shing}

Adequate Encryption Standard

hashtagFlag: rgbCTF{brut3_f0rc3_is_4LW4YS_th3_4nsw3r(but_with_0ptimiz4ti0ns)}

Occasionally Tested Protocol

rubikcbc

hashtagrgbCTF{!IP_over_Avian_Carriers_with_QoS!}

N-AES

hashtagFlag: rgbCTF{i_d0nt_7hink_7his_d03s_wh47_y0u_7hink_i7_d03s}

I Love Rainbows

hashtagFlag: rgbCTF{4lw4ys_us3_s4lt_wh3n_h4shing}

crypto

Shakespeare Play, Lost (and found!)

hashtagFlag: rgbCTF{itsanrgbtreeeeeee!}

Adequate Encryption Standard

hashtagFlag: rgbCTF{brut3_f0rc3_is_4LW4YS_th3_4nsw3r(but_with_0ptimiz4ti0ns)}

(rgbctf/crypto/e.md)

Grab your Jisho

hashtagFlag: rgbctf{~|~yominikui~|~} (meaning: illegible)

rubikcbc

hashtagrgbCTF{!IP_over_Avian_Carriers_with_QoS!}

N-AES

hashtagFlag: rgbCTF{i_d0nt_7hink_7his_d03s_wh47_y0u_7hink_i7_d03s}

Occasionally Tested Protocol

hashtagFlag: rgbCTF{random_is_not_secure}

Flag: rgbctf{~|~yominikui~|~} (meaning: illegible)

Flag: rgbCTF{itsanrgbtreeeeeee!}

Flag: rgbCTF{4lw4ys_us3_s4lt_wh3n_h4shing}

Flag: rgbCTF{brut3_f0rc3_is_4LW4YS_th3_4nsw3r(but_with_0ptimiz4ti0ns)}

rgbCTF{!IP_over_Avian_Carriers_with_QoS!}

Flag: rgbCTF{i_d0nt_7hink_7his_d03s_wh47_y0u_7hink_i7_d03s}

Flag: rgbCTF{4lw4ys_us3_s4lt_wh3n_h4shing}

Flag: rgbCTF{itsanrgbtreeeeeee!}

Flag: rgbCTF{brut3_f0rc3_is_4LW4YS_th3_4nsw3r(but_with_0ptimiz4ti0ns)}

Flag: rgbctf{~|~yominikui~|~} (meaning: illegible)

rgbCTF{!IP_over_Avian_Carriers_with_QoS!}

Flag: rgbCTF{i_d0nt_7hink_7his_d03s_wh47_y0u_7hink_i7_d03s}

Flag: rgbCTF{random_is_not_secure}