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Warm-up·easy·15 pts
Single-byte XOR
A message XORed with one repeated byte. There's a shortcut hiding in how every flag on this site starts.
This one has actually been "encrypted" — every byte of the flag was XORed with the same single secret byte.
You don't know the key. But you do know every flag on this site starts with the four characters cct{.
Ciphertext (hex)
49495e515943444d1b4f7548535e4f75521a58751b59755d4f1e4157
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Background on this technique
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An Old Habit →Someone on the team still encrypts things the way Julius Caesar did. Read their message.