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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
10 solves
Submissions (latest 3)
toomer

SOLVED!

Sep 21, 6:49 PM

kakur41

SOLVED!

Sep 21, 6:27 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🌱
2,211 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
41 solves
19-21
hiikunzhiikunz
nested eval
Misc
Hard
39 solves
 
hiikunzhiikunz
nested eval
Misc
Hard
39 solves
22-24
2501
The 3rd
Crypto
Hard
10 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
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4
Coming soon

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Writeups

Writeup for flag obfuscation

enesbasmaci

en
flag obfuscation

1 hour ago

Rows:

Safe Prime

Topic: [Mirror] SECCON Beginners CTFReleased: Dec 13, 2025

294 solves
Crypto

by

ptr-yudai

ptr-yudai

USER

SOLVED AT

ferrumdx3

2026/09/04 10:24

2026/08/22 10:38

2026/08/21 12:03

2026/08/15 10:28

2026/08/13 11:18

2026/08/10 18:35

2026/08/04 15:15

2026/08/03 20:50

2026/07/17 13:02

2026/07/16 01:21

2026/07/13 09:27

2026/06/26 15:00

2026/06/16 09:10

2026/06/13 12:57

2026/06/04 02:17

2026/06/01 03:40

2026/05/29 08:40

2026/05/27 13:59

2026/05/27 01:25

2026/05/24 12:08

2026/05/24 06:53

2026/05/21 06:46

2026/05/19 05:30

2026/05/17 05:04

2026/05/15 19:16

Rows:

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