IrORversible

##Challenge Name: IrORversible

###Solves

• >Solves: 222
• >Points: 50

###Description

So reversible it's practically irreversible.

Connection:

nc irrorversible.ctf.intigriti.io 1330

###Approach

1. >

   Initial Observations:

   • >Based on the challenge description, the name suggested that the challenge involved XOR encryption.
2. >

   Testing Input and Observing Output:

   • >Connected to the provided server using

     netcat

     :
     bash

     nc irrorversible.ctf.intigriti.io 1330
   • >Sent a large number of

     a

     characters (

     aaaa...

     ), and the server responded with a hexadecimal string:

     280f41392e334116044115131412154d410f0e410f04040541150e4107080609154d412308151241070d081141000f054105000f02044d41080f41050018410e13410f080609154f41350e41021300020a4115090812410a04184d41180e14410c141215410419110d0e13044d41282f352826332835281a03555450023e1951133e160955565e1c4d4109080505040f4100154108151241020e78

3. >

   XOR Key Analysis:

   • >XOR encryption works by applying the same key to both encrypt and decrypt data. To decipher the response, we needed to determine the key.
4. >

   Reversing the XOR Operation:

   • >

     By XORing the hex response with the known input (

     aaaa...

     ), we could reveal the original message (including the flag).

     

5. >

   Flag Extraction:

   • >Decoding the result revealed the flag as part of the original decrypted text.

   Flag:

   INTIGRITI{b451c_x0r_wh47?}

###Flag

INTIGRITI{b451c_x0r_wh47?}