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Daily AlpacaHack

A daily CTF challenge with a fun new puzzle every day

What is Daily AlpacaHack?

We publish one simple, beginner-friendly or educational CTF challenge every day!

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Today's Challenge
rsk0315
Bounds Checking
Pwn
Hard
16 solves
Submissions (latest 3)
cyanos

SOLVED!

May 9, 6:15 PM

tadanobutubutu

SOLVED!

May 9, 5:32 PM

Leaderboard

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admin
AlpacaHack 2100
Misc
Welcome
1,761 solves
Upcoming challenges reveal the , , and in advance.
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Writeups

tadanobutubutu

Writeup for reused n

tadanobutubutu

ja
reused n

3 hours ago

kakur41

Writeup for Daily AlpacaHack 5/3-5/9

ja
reused n

+6

5 hours ago

Writeup for Vending Machine

author
ja

7 hours ago

tadanobutubutu

Writeup for Vending Machine

Daily AlpacaHackに挑戦するつくよみちゃん 05/08 misc/Vending Machine/baumroll1234

Daily AlpacaHackに挑戦するつくよみちゃん 05/07 misc/Permission Denied 3/minaminao

Rows:

RBG

Topic: RSA, LCGReleased: Dec 30, 2025

126 solves
Crypto
Very Hard

by

soon-haari

soon-haari

RBG stands for RSA + SBG + LCG!
To learn about them, please check out lecture1.mp4.

Beginner Hint: Very Hard (AI-translated)
  • This challenge's difficulty is Very Hard.
  • Very Hard is assigned to challenges that require substantial reasoning and are difficult to solve by simply applying standard techniques directly.
  • This challenge is one of them. It is an interesting challenge that requires some insight, so please give it a try.
  • For beginners, solving it entirely on your own will be difficult. If you get stuck, we recommend making good use of AI as needed, deepening your understanding little by little, and looking for a starting point for the solution.
rbg.tar.gz
descriptionsolveswriteups