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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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Today's Challenge
2501
Lean as a Service
Misc
Medium
36 solves
Submissions (latest 3)
onotch

SOLVED!

Oct 31, 12:24 PM

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.

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admin
AlpacaHack 2100
Misc
Welcome🌱
2,327 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
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
36 solves
1
admin
Planned topicWelcome
Misc
Welcome🌱

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Writeups

claritys

Writeup for alloc-101

claritys

en
alloc-101

2 hours ago

claritys

Writeup for login-bonus (English)

en

3 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:

alloc-101

Topic: HeapReleased: Dec 19, 2025

266 solves
Pwn
Hard3.5

by

k0080

k0080

Writeups

k0080

Author's Writeup for alloc-101

k0080

author
en

2025/12/22 02:14


claritys

Writeup for alloc-101

en

2 hours ago


kakur41

Writeup for alloc-101

ja

2025/12/19 15:03



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