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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
35 solves
Submissions (latest 3)
jam-yabusame

SOLVED!

Oct 31, 1:16 AM

ctf-udon

SOLVED!

Oct 30, 3:40 PM

Leaderboard

Try the first challenge

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

View challenge
admin
AlpacaHack 2100
Misc
Welcome🌱
2,327 solves
Upcoming challenges reveal the , , and in advance.
Prev

Oct 2026

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

claritys

Writeup for alloc-101

claritys

en
alloc-101

45 minutes ago

claritys

Writeup for login-bonus (English)

en

2 hours ago

claritys

Writeup for Integer Writer (with brief explanation)

tadanobutubutu

Writeup for what is my pointer 4

tadanobutubutu

Writeup for Σecret

ja

2026/10/24 16:37

Rows:

curl as a service

Topic: curlReleased: May 15, 2026

164 solves
WebMisc
Medium5.0

by

tan90909090

tan90909090

USER

SOLVED AT

9b9fc

19 hours ago

2026/10/22 14:31

2026/10/13 18:43

2026/10/11 14:41

2026/10/11 11:15

2026/10/04 08:40

2026/09/29 16:56

2026/09/10 14:29

2026/09/09 07:27

2026/09/07 10:45

2026/09/01 12:00

2026/08/25 08:55

2026/08/25 02:29

2026/08/23 04:59

2026/08/14 07:02

2026/08/14 05:06

2026/08/13 14:49

2026/07/31 10:30

2026/07/24 12:41

2026/07/21 11:17

2026/07/09 08:28

2026/07/09 04:07

2026/07/08 14:41

2026/07/08 09:03

2026/07/08 06:43

Rows:

descriptionsolveswriteups