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Daily AlpacaHack

A CTF challenge series with fun puzzles to enjoy every day

What is Daily AlpacaHack?

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

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Solve each challenge within its time window to appear on the leaderboard.

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Today's Challenge
hiikunzhiikunz
AESAESAESAESAESAES
Crypto
Hard
17 solves
Submissions (latest 3)
haihuiliyuyuan

SOLVED!

Aug 6, 1:02 AM

Leaderboard

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Is this your first CTF? Let's begin by tackling the first challenge released on Daily AlpacaHack.

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admin
AlpacaHack 2100
Misc
Welcome🌱
2,067 solves
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Happy Birthday

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Rows:

Sugoi Flag Checker

Topic: ELFReleased: Dec 12, 2025

228 solves
Rev
Hard5.5

by

chocorusk

chocorusk

A super flag checker that uses a super cryptographic algorithm.

Beginner Hint 1 (AI-translated)
  • chal is an ELF executable. First, try decompiling it with a reverse engineering tool such as IDA Free, Ghidra, or Binary Ninja.
  • Also, this challenge is Hard, so if you are a beginner, we recommend using AI as needed.
  • For example, you can drag and drop the binary into ChatGPT and ask it to help with the analysis.
Beginner Hint 2: Spoiler Alert! (AI-translated)
  • Actually, you can solve this challenge without understanding most of the cryptographic processing.
  • Focus on what strings are being compared by the strcmp function.
chal

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