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Puzzle 4

XOR

Puzzle

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# Puzzle 4 #
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00 34 CALLVALUE
01 38 CODESIZE
02 18 XOR
03 56 JUMP
04 FD REVERT
05 FD REVERT
06 FD REVERT
07 FD REVERT
08 FD REVERT
09 FD REVERT
0A 5B JUMPDEST
0B 00 STOP
? Enter the value to send: (0)

Solution

JUMP to XOR(msg.value, 12).
The objective is to jump to address 0x0A. Recall that XOR(msg.value, 12) = 0x0A implies msg.value = XOR(0x0A, 12). Do it in Python:
XOR(0x0A, 12)
The correct input is 6.
Last modified 1d ago