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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
2501
Lean as a Service
Misc
Medium
24 solves
Submissions (latest 3)
rsk0315

SOLVED!

Oct 29, 5:16 PM

serioton

SOLVED!

Oct 29, 2:43 PM

Leaderboard

Try the first challenge

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🌱
2,321 solves
Upcoming challenges reveal the , , and in advance.
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Oct 2026

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k0080k0080
what is my pointer 2
Pwn
Hard
49 solves
1
admin
Baby Alpaca
Misc
Welcome🌱
170 solves
2
tan90909090tan90909090
C# File-based app
Rev
Easy🌱
85 solves
3-4
2501
Shared Prime
Crypto
Medium
90 solves
5-8
tan90909090tan90909090
fsbase modification
Pwn
Hard
62 solves
9-12
2501
Almost Shared Prime
Crypto
Hard
44 solves
 
2501
Almost Shared Prime
Crypto
Hard
44 solves
13-14
tan90909090tan90909090
cowsay jail
Misc
Medium
62 solves
15-18
hiikunzhiikunz
decreasing
Misc
Hard
34 solves
19-22
tan90909090tan90909090
x32 ABI flag checker
Rev
Hard
33 solves
23-24
pppp4649pppp4649
Σecret
Crypto
Easy🌱
50 solves
25-28
k0080k0080
what is my pointer 4
Pwn
Hard
38 solves
 
k0080k0080
what is my pointer 4
Pwn
Hard
38 solves
29-31
2501
Lean as a Service
Misc
Medium
24 solves
1
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Writeups

Writeup for Alpaca Quest

haruhana

ja
Alpaca Quest

15 hours ago

tadanobutubutu

Writeup for Σecret

ja

2026/10/24 16:37

tadanobutubutu

Writeup for x32 ABI flag checker

Rows:

Linear Coffee Generator

Topic: LCGReleased: Jan 30, 2026

126 solves
Crypto
Hard5.5

by

yu212

yu212

USER

SOLVED AT

puagg99

2026/10/11 06:04

2026/09/14 11:07

2026/07/11 11:23

2026/07/10 10:10

2026/07/02 07:11

2026/06/30 11:55

2026/06/16 09:42

2026/05/15 07:51

2026/05/04 19:13

2026/04/29 14:36

2026/04/21 09:08

2026/04/11 03:09

2026/04/07 17:19

2026/04/03 12:07

2026/04/01 18:30

2026/03/31 21:17

2026/03/22 16:05

2026/03/15 13:52

2026/03/11 17:50

2026/03/09 15:34

2026/03/04 15:38

2026/02/16 14:21

2026/02/14 08:01

2026/02/11 13:50

2026/02/09 14:24

Rows:

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