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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!

Join Anytime

Solve within 24 hours of release to appear on the leaderboard.

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Discussion with friends or AI is welcome (account sharing is prohibited).

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Today's Challenge
tchentchen
Looks like Alpacahack
Web
Medium
23 solves
Submissions (latest 3)
tadanobutubutu
tadanobutubutu

SOLVED!

Jun 16, 5:59 PM

serioton

SOLVED!

Jun 16, 5:29 PM

hiikunz

SOLVED!

Jun 16, 5:27 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🌱
1,892 solves
Upcoming challenges reveal the , , and in advance.
Prev

Jun 2026

Next
Solved
Unsolved
Upcoming
Mon
Tue
Wed
Thu
Fri
Sat
Sun
1
admin
Half-Year Recap
Misc
Welcome🌱
217 solves
2
minaminaominaminao
Cache Me If You Can
Web
Easy🌱
182 solves
3
minaminaominaminao
vm1
Misc
Medium
92 solves
4
pppp4649pppp4649
Small e
Crypto
Easy🌱
123 solves
5
minaminaominaminao
RPS GAME
Misc
Crypto
Medium
92 solves
6
nozokare
Flag for localhost
Web
Easy🌱
145 solves
7
tan90909090tan90909090
C++ flag checker
Rev
Hard
79 solves
8
shiragishiragi
Guess IP
Misc
Easy🌱
126 solves
9
nozokare
A Piece of DHKE
Crypto
Medium
78 solves
10
shiragishiragi
chmod-swapper
Misc
Medium
79 solves
11
tchentchen
Alpaca Certification
Web
Easy🌱
142 solves
12
rsk0315
Floating Equality
Misc
Medium
89 solves
13
pppp4649pppp4649
Elliptic Equation
Crypto
Hard
55 solves
14
tchentchen
CAuth
Web
Hard
61 solves
15
minaminaominaminao
SITE/2
Web
Easy🌱
102 solves
16
tan90909090tan90909090
Xored PNG
Misc
Medium
78 solves
17
tchentchen
Looks like Alpacahack
Web
Medium
23 solves
18
Coming soon
19
Coming soon
20
nozokare
Planned topicRNG
Crypto
Hard
21
Planned topicHeap
Pwn
Hard
22
Coming soon
23
Coming soon
24
Coming soon
25
Coming soon
26
Coming soon
28
Planned topicTBA
Pwn
Hard
29
Coming soon
30
Coming soon
1
Coming soon
2
Coming soon
3
Coming soon
4
Coming soon
5
Coming soon

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Writeups

tadanobutubutu

Writeup for Xored PNG

tadanobutubutu

ja
Xored PNG

1 hour ago

Daily AlpacaHackに挑戦するつくよみちゃん 06/16/Xored PNG/tan90909090

tadanobutubutu

Writeup for SITE/2

nirvana

Writeup for SITE/2

ja

20 hours ago

nirvana

Writeup for CAuth

ja

2026/06/14 23:23

tadanobutubutu

Writeup for CAuth

ja

2026/06/14 15:01

tadanobutubutu

Writeup for Elliptic Equation

Writeup for Daily AlpacaHack 6/1-6/7

ja
Small e

+6

2026/06/14 09:10

Rows:

Time Travelers' OTP

Topic: One-Time PasswordReleased: May 22, 2026

96 solves
Web
Medium

by

nozokare

Will AlpacaHack still be around 4000 years from now?

time-travelers-otp.tar.gz

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