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

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No solved challenges yet.

Today's Challenge

Submissions (latest 3)

omame3

SOLVED!

Mar 6, 11:39 AM

tab

SOLVED!

Mar 6, 11:18 AM

mizore-fuyu

SOLVED!

Mar 6, 11:16 AM

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.

Jan 2026

Solved

Unsolved

Upcoming

Mon

Tue

Wed

Thu

Fri

Sat

Sun

kanon

one-p-rsa

Crypto

Easy

209 solves

soon-haari

RBG

Crypto

Very Hard

118 solves

admin

108

Misc

Easy

265 solves

admin

Happy New Year

Misc

Welcome

497 solves

kanon

super-tomato

Crypto

Easy

344 solves

hiikunz

Ruby Flag Checker

Rev

Easy

264 solves

minaminao

Fushigi Crawler

Web

Easy

304 solves

kurenaif

Encoding Basics

Misc

Crypto

Easy

285 solves

minaminao

jailiaj

Misc

Easy

259 solves

hiikunz

Square RSA

Crypto

Medium

216 solves

ark

secret-table

Web

Medium

247 solves

hiikunz

SwapSwap

Misc

Easy

255 solves

theoremoon

RSA2026

Crypto

Medium

192 solves

keymoon

crazython

Rev

Medium

169 solves

hiikunz

Basic Buffer Overflow

Pwn

Medium

165 solves

tchen

I wanna be the Admin

Web

Easy

251 solves

ark

free-comment

Misc

Hard

144 solves

hiikunz

Five Alpacas

Crypto

Easy

181 solves

k0080

Short Writer

Pwn

Hard

115 solves

minaminao

Base Length

Misc

Medium

147 solves

hiikunz

dice roll

Web

Medium

188 solves

chocorusk

ChaChaCha

Crypto

Medium

150 solves

k0080

system-v

Rev

Hard

114 solves

ark

dockerstack

Misc

Easy

170 solves

hiikunz

Animal Viewer

Web

Medium

142 solves

minaminao

Bashrunner

Misc

Hard

115 solves

yu212

Paca Paca Authenticator

Crypto

Medium

118 solves

tchen

Stateless Auth

Web

Medium

155 solves

keymoon

git gc

Misc

Medium

141 solves

chocorusk

ToyPQC

Crypto

Hard

101 solves

tchen

No JS

Web

Medium

122 solves

k0080

shellcode-101

Pwn

Medium

120 solves

yu212

Linear Coffee Generator

Crypto

Hard

106 solves

ark

optimal-sort

Misc

Hard

96 solves

admin

Camelidae

Misc

Welcome

333 solves

Want a harder challenge?

Go to B-SIDE

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