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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
The 3rd
Crypto
Hard
6 solves
Submissions (latest 3)
kurgm
kurgm

SOLVED!

Sep 21, 3:52 PM

serioton

SOLVED!

Sep 21, 3:19 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🌱
2,211 solves
Upcoming challenges reveal the , , and in advance.
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Sep 2026

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tchentchen
Springing
Web
Medium
74 solves
1
admin
QUIZ ALPACASHOCK
Misc
Welcome🌱
124 solves
2
hiikunzhiikunz
base 16-32-64
Misc
Easy🌱
101 solves
3-4
tan90909090tan90909090
Let's Shut Down Linux
Misc
Medium
63 solves
5
baumroll1234
6-8
minaminaominaminao
Bitflip RSA
Crypto
Hard
56 solves
 
minaminaominaminao
Bitflip RSA
Crypto
Hard
56 solves
9-11
minaminaominaminao
\^o^/
Misc
Hard
43 solves
12-13
tan90909090tan90909090
sin function vs. fsin instruction
Rev
Misc
Medium
55 solves
14-15
tan90909090tan90909090
integer division
Misc
Medium
69 solves
16-18
edwowmathedwowmath
neighboRhood_diStAnce
Crypto
Hard
40 solves
19-21
hiikunzhiikunz
nested eval
Misc
Hard
39 solves
 
hiikunzhiikunz
nested eval
Misc
Hard
39 solves
22-24
2501
The 3rd
Crypto
Hard
6 solves
25
Coming soon
26
Coming soon
27
Coming soon
28
Coming soon
29
Coming soon
30
Coming soon
1
Coming soon
2
Coming soon
3
Coming soon
4
Coming soon

Want a harder challenge?

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Writeups

shiragi

Writeup for nested eval

shiragi

ja
nested eval

1 hour ago

gattoartz

Writeup for Alpaca Bank

gattoartz

Writeup for Read Assembly

gattoartz

Writeup for hit-and-miss

gattoartz

Writeup for simpleoverflow

curetwinkle

Writeup for simple ROP(アセンブリ解説多め)

ja

2026/09/15 03:55

Rows:

Alpaca Bank

Topic: GeneralReleased: Dec 11, 2025

423 solves
Web
Medium2.0

by

hiikunz

hiikunz

USER

SOLVED AT

wocucumber

7 hours ago

2026/09/16 06:34

2026/09/10 05:59

2026/09/09 07:41

2026/09/09 06:22

2026/09/09 03:15

2026/09/08 13:12

2026/08/31 07:22

2026/08/30 16:36

2026/08/30 01:33

2026/08/27 11:18

2026/08/25 01:12

2026/08/24 02:18

2026/08/23 08:04

2026/08/21 15:21

2026/08/21 05:29

2026/08/20 17:47

2026/08/18 08:09

2026/08/16 22:57

2026/08/09 07:25

2026/08/08 11:20

2026/08/07 16:07

2026/08/07 05:27

2026/08/01 09:15

2026/08/01 08:27

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