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Home FinalTrace 2025 Mirror Shatter
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Mirror Shatter

  • Category: Web
  • Author: Kirubahari

Challenge Description

The Challenge is about web enumeration and find the hidden endpoints and parameters to get the flag

Solution

Initial Analysis

What I did first - enumeration, bruteforcing for endpoints

Tools Used

  • ffuf
  • base64
  • python

Step-by-Step Solution

Step 1: Finding the endpoint

1
ffuf -u "http://$IP:$PORT/FUZZ" -w WORDLIST --ic

It gives the hidden endpoint

Step 2: Fidning the parameter

1
ffuf -u "http://$IP:$PORT/mirror?FUZZ=true" -w WORDLIST --ic -fs int(x)

Which gievs the hiddenendpoint which downlaods the zip file which has the encoded flag

Step 3: Decoing

1
cat flag.txt | base64 -d

which gives the decoded dna encoded text decoding gives the flag

Script

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import sys

MAP = {
    'A': '00',
    'C': '01',
    'G': '10',
    'T': '11'
}

def dna_to_bytes(dna: str) -> bytes:
    dna = ''.join(dna.split())
    if len(dna) % 4 != 0:
        raise ValueError("DNA length not multiple of 4 (each byte = 4 nucleotides).")
    bits = ''.join(MAP[nuc] for nuc in dna)
    out = bytes(int(bits[i:i+8], 2) for i in range(0, len(bits), 8))
    return out

def main():
    if len(sys.argv) == 2 and sys.argv[1] != '-':
        s = open(sys.argv[1], 'r').read()
    else:
        s = sys.stdin.read()
    try:
        b = dna_to_bytes(s)
        print(b.decode('utf-8'))
    except Exception as e:
        print("Decoding failed:", e, file=sys.stderr)
        try:
            b = dna_to_bytes(s.strip())
            import binascii
            print("HEX:", binascii.hexlify(b).decode())
        except:
            pass
        sys.exit(1)

if __name__ == '__main__':
    main()

Flag

1
CYS{B43aking_th3_m1rr0r_1$_c00l}

Flag

CYS{B43aking_th3_m1rr0r_1$_c00l}
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