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Binary ExploitationLesson + challenge Live machineFree

Return to Sender

Overwrite the return address. Return where you were never meant to go.

The classic first step into binary exploitation: overflow a stack buffer on a tiny TCP service and overwrite the saved return address to call a win() function that prints the flag. The binary is yours to analyse.

Difficulty
Easy
Estimated time
45 min
Points
150 pts
Completions
Completed by 1 player
Authors
By Cyber Academy 4 U
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What you will learn

  • Explain how the call stack stores a function's return address
  • Overflow a stack buffer to overwrite that saved return address
  • Read a fixed (No-PIE) function address from a binary
  • Find the overflow offset and write a first ret2win exploit

What is inside

  1. Task 1 · Return to Sender1 question

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