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nullptr - ALLES CTF 2020

Cyb0rG
2020-09-09
Pwn / File Structure

tl;dr

  • Overwrite mmap_threshold with null and trim top chunk size.
  • Null out last 2 bytes of stdin’s _IO_buf_base and brute force to get allocation on stdin.
  • Overwrite one of the jump tables with win function to get shell.
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ALLESCTF File Structure

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