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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
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
10 solves
25
Coming soon
26
Coming soon
27
Coming soon
28
Coming soon
29
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30
Coming soon
1
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2
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Writeups

Writeup for flag obfuscation

enesbasmaci

en
flag obfuscation

51 minutes ago

Rows:

Flag Printer 2100

Topic: ELFReleased: Dec 15, 2025

291 solves
Rev
Medium4.5

by

hiikunz

hiikunz

This program prints the flag after sleeping for 75 years. It means you have to wait until the year 2100 to get the flag!

print_flag

Please sign in to submit the flag.

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