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.

Not a Competition

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

Solution Sharing Rules

Sharing solutions is allowed only after 24 hours have passed since release.

Solve stats

/19

No solved challenges yet.

Today's Challenge

Submissions (latest 3)

baumroll1234

SOLVED!

Jun 18, 7:31 PM

toomer

SOLVED!

Jun 18, 7:22 PM

tenagazaru

SOLVED!

Jun 18, 5:15 PM

Leaderboard

Period

Try the first challenge

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

Upcoming challenges reveal the , , and in advance.

Jun 2026

Solved

Unsolved

Upcoming

Mon

Tue

Wed

Thu

Fri

Sat

Sun

admin

Half-Year Recap

Misc

Welcome🌱

222 solves

minaminao

Cache Me If You Can

Web

Easy🌱

183 solves

minaminao

vm1

Misc

Medium

92 solves

pppp4649

Small e

Crypto

Easy🌱

126 solves

minaminao

RPS GAME

Misc

Crypto

Medium

94 solves

nozokare

Flag for localhost

Web

Easy🌱

146 solves

tan90909090

C++ flag checker

Rev

Hard

81 solves

shiragi

Guess IP

Misc

Easy🌱

130 solves

nozokare

A Piece of DHKE

Crypto

Medium

80 solves

shiragi

chmod-swapper

Misc

Medium

79 solves

tchen

Alpaca Certification

Web

Easy🌱

145 solves

rsk0315

Floating Equality

Misc

Medium

89 solves

pppp4649

Elliptic Equation

Crypto

Hard

57 solves

tchen

CAuth

Web

Hard

61 solves

minaminao

SITE/2

Web

Easy🌱

110 solves

tan90909090

Xored PNG

Misc

Medium

82 solves

tchen

Looks like Alpacahack

Web

Medium

71 solves

shiragi

Catrunner 2

Misc

Easy🌱

84 solves

minaminao

Flag Printer 20XX

Misc

Medium

21 solves

nozokare

Planned topicRNG

Crypto

Hard

k0080

Planned topicHeap

Pwn

Hard

minaminao

Planned topicSecret Sharing

Crypto

Easy🌱

tchen

Planned topicNginx

Web

Medium

Coming soon

colza

Planned topicArchive

Misc

Easy🌱

Coming soon

bubu

Planned topicClient-Side

Web

Hard

pppp4649

Planned topicTBA

Pwn

Hard

Coming soon

admin

Planned topicWelcome

Misc

Welcome🌱

Coming soon

Want a harder challenge?

Go to B-SIDE

Writeups

Daily AlpacaHackに挑戦するつくよみちゃん 06/18/Catrunner 2/shiragi

tsukuyomi-chan

Catrunner 2

4 hours ago

Writeup for Looks like Alpacahack

nirvana

Looks like Alpacahack

18 hours ago

Daily AlpacaHackに挑戦するつくよみちゃん 06/17/Looks like Alpacahack/tchen

tsukuyomi-chan

Looks like Alpacahack

2026/06/17 17:12

Writeup for Looks like Alpacahack

baumroll1234

Looks like Alpacahack

2026/06/17 16:10

Writeup for Looks like Alpacahack

goroshirow

Looks like Alpacahack

2026/06/17 15:07

Writeup for Xored PNG

baumroll1234

Xored PNG

2026/06/16 20:22

Writeup for Xored PNG

tadanobutubutu

Xored PNG

2026/06/16 17:17

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

tsukuyomi-chan

Xored PNG

2026/06/16 17:06

Writeup for SITE/2

tadanobutubutu

SITE/2

2026/06/16 10:33

Writeup for SITE/2

nirvana

SITE/2

2026/06/15 21:55

Rows:

Flag Printer 20XX

Topic: PythonReleased: Jun 19, 2026

21 solves

Misc

Medium

minaminao

USER	SOLVED AT
baumroll1234	just now
toomer	9 minutes ago
tenagazaru	2 hours ago
kurgm	2 hours ago
hiikunz	2 hours ago
cocoa	3 hours ago
rsk0315	3 hours ago
kakur41	3 hours ago
bsvac	3 hours ago
mak0tan	3 hours ago
edwowmath	3 hours ago
mti	3 hours ago
goroshirow	3 hours ago
kitatai	3 hours ago
nanashiku	3 hours ago
kumabear	3 hours ago
itsuki-t	3 hours ago
sig-255	3 hours ago
panya	4 hours ago
umineko	4 hours ago
koufu193	4 hours ago

Rows:

description solves