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Daily AlpacaHack

A CTF challenge series with fun puzzles to enjoy every day

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We regularly publish simple, beginner-friendly or educational CTF challenges!

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Today's Challenge
tan90909090tan90909090
x32 ABI flag checker
Rev
Hard
3 solves
Submissions (latest 3)
tadanobutubutu
tadanobutubutu

SOLVED!

Oct 18, 3:28 PM

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Rows:

x32 ABI flag checker

Topic: ABIReleased: Oct 19, 2026

3 solves
Rev
Hard8.0

by

tan90909090

tan90909090

This is a flag checker built to use the x32 ABI!

NOTE: There is a plan to remove the x32 ABI from the Linux kernel. Consequently, it may become impossible to execute the provided file for this challenge in the future. However, since this challenge can also be solved through static analysis alone, I encourage you to give it a try.

Beginner Hint: How to Approach the Challenge
  • Some analysis tools do not handle x32 ABI binaries well. For example, they may fail to execute, disassemble using a wrong ISA, or produce a decompilation output that is difficult to read.
  • If you encounter such issues, trying a different tool is one possible solution.
x32-abi-flag-checker

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descriptionsolves